diff --git a/lib/jasmine-core/boot/boot.js b/lib/jasmine-core/boot/boot.js
index fb41d0c7..e3f95062 100644
--- a/lib/jasmine-core/boot/boot.js
+++ b/lib/jasmine-core/boot/boot.js
@@ -38,6 +38,9 @@
       return env.spyOn(obj, methodName);
     },
 
+    clock: function() {
+      return env.clock;
+    },
 
     jsApiReporter: new jasmine.JsApiReporter(jasmine)
   };
diff --git a/lib/jasmine-core/jasmine.js b/lib/jasmine-core/jasmine.js
index f3316038..dae085c3 100644
--- a/lib/jasmine-core/jasmine.js
+++ b/lib/jasmine-core/jasmine.js
@@ -108,8 +108,8 @@ jasmine.MessageResult.prototype.toString = function() {
 /**
  * Getter for the Jasmine environment. Ensures one gets created
  */
-jasmine.getEnv = function() {
-  var env = jasmine.currentEnv_ = jasmine.currentEnv_ || new jasmine.Env();
+jasmine.getEnv = function(options) {
+  var env = jasmine.currentEnv_ = jasmine.currentEnv_ || new jasmine.Env(options);
   //jasmine. singletons in here (setTimeout blah blah).
   return env;
 };
@@ -519,12 +519,17 @@ jasmine.buildExpectationResult = function(params) {
  * @constructor
  */
 (function() {
-  jasmine.Env = function() {
+  jasmine.Env = function(options) {
+    options = options || {};
     var self = this;
+    var global = options.global || jasmine.getGlobal();
+
+    this.clock = new jasmine.Clock(global, new jasmine.DelayedFunctionScheduler());
+
     var suiteConstructor = jasmine.Suite;
     var isSuite = function(thing) {
       return thing instanceof suiteConstructor;
-    }
+    };
     this.jasmine = jasmine;
     this.currentRunner_ = new jasmine.Runner(this, isSuite);
     this.spies_ = [];
@@ -610,8 +615,7 @@ jasmine.buildExpectationResult = function(params) {
         afterFns: afterFns(suite),
         expectationFactory: expectationFactory,
         exceptionFormatter: exceptionFormatter,
-        //TODO: move spec creation to more appropriate level and remove this shim
-        resultCallback: function(result) { self.currentSpec = null; suite.specComplete(result); },
+        resultCallback: specResultCallback,
         fullNameFactory: function(spec) { return fullNameFactory(spec, suite) },
         startCallback: startCallback,
         description: description,
@@ -625,8 +629,13 @@ jasmine.buildExpectationResult = function(params) {
       }
 
       return spec;
-    };
 
+      function specResultCallback(result) {
+        self.clock.uninstall();
+        self.currentSpec = null;
+        suite.specComplete(result);
+      }
+    };
 
     var queueConstructor = jasmine.Queue;
     var queueFactory = function() {
@@ -638,12 +647,6 @@ jasmine.buildExpectationResult = function(params) {
 
   };
 
-
-  jasmine.Env.prototype.setTimeout = jasmine.setTimeout;
-  jasmine.Env.prototype.clearTimeout = jasmine.clearTimeout;
-  jasmine.Env.prototype.setInterval = jasmine.setInterval;
-  jasmine.Env.prototype.clearInterval = jasmine.clearInterval;
-
   //TODO: shim Spec addMatchers behavior into Env. Should be rewritten to remove globals, etc.
   jasmine.Env.prototype.addMatchers = function(matchersPrototype) {
     var parent = this.matchersClass;
@@ -1480,190 +1483,6 @@ jasmine.Matchers.ObjectContaining.prototype.jasmineMatches = function(other, mis
 jasmine.Matchers.ObjectContaining.prototype.jasmineToString = function () {
   return "<jasmine.objectContaining(" + jasmine.pp(this.sample) + ")>";
 };
-// Mock setTimeout, clearTimeout
-// Contributed by Pivotal Computer Systems, www.pivotalsf.com
-
-jasmine.FakeTimer = function() {
-  this.reset();
-
-  var self = this;
-  self.setTimeout = function(funcToCall, millis) {
-    self.timeoutsMade++;
-    self.scheduleFunction(self.timeoutsMade, funcToCall, millis, false);
-    return self.timeoutsMade;
-  };
-
-  self.setInterval = function(funcToCall, millis) {
-    self.timeoutsMade++;
-    self.scheduleFunction(self.timeoutsMade, funcToCall, millis, true);
-    return self.timeoutsMade;
-  };
-
-  self.clearTimeout = function(timeoutKey) {
-    self.scheduledFunctions[timeoutKey] = jasmine.undefined;
-  };
-
-  self.clearInterval = function(timeoutKey) {
-    self.scheduledFunctions[timeoutKey] = jasmine.undefined;
-  };
-
-};
-
-jasmine.FakeTimer.prototype.reset = function() {
-  this.timeoutsMade = 0;
-  this.scheduledFunctions = {};
-  this.nowMillis = 0;
-};
-
-jasmine.FakeTimer.prototype.tick = function(millis) {
-  var oldMillis = this.nowMillis;
-  var newMillis = oldMillis + millis;
-  this.runFunctionsWithinRange(oldMillis, newMillis);
-  this.nowMillis = newMillis;
-};
-
-jasmine.FakeTimer.prototype.runFunctionsWithinRange = function(oldMillis, nowMillis) {
-  var scheduledFunc;
-  var funcsToRun = [];
-  for (var timeoutKey in this.scheduledFunctions) {
-    scheduledFunc = this.scheduledFunctions[timeoutKey];
-    if (scheduledFunc != jasmine.undefined &&
-        scheduledFunc.runAtMillis >= oldMillis &&
-        scheduledFunc.runAtMillis <= nowMillis) {
-      funcsToRun.push(scheduledFunc);
-      this.scheduledFunctions[timeoutKey] = jasmine.undefined;
-    }
-  }
-
-  if (funcsToRun.length > 0) {
-    funcsToRun.sort(function(a, b) {
-      return a.runAtMillis - b.runAtMillis;
-    });
-    for (var i = 0; i < funcsToRun.length; ++i) {
-      try {
-        var funcToRun = funcsToRun[i];
-        this.nowMillis = funcToRun.runAtMillis;
-        funcToRun.funcToCall();
-        if (funcToRun.recurring) {
-          this.scheduleFunction(funcToRun.timeoutKey,
-              funcToRun.funcToCall,
-              funcToRun.millis,
-              true);
-        }
-      } catch(e) {
-      }
-    }
-    this.runFunctionsWithinRange(oldMillis, nowMillis);
-  }
-};
-
-jasmine.FakeTimer.prototype.scheduleFunction = function(timeoutKey, funcToCall, millis, recurring) {
-  this.scheduledFunctions[timeoutKey] = {
-    runAtMillis: this.nowMillis + millis,
-    funcToCall: funcToCall,
-    recurring: recurring,
-    timeoutKey: timeoutKey,
-    millis: millis
-  };
-};
-
-/**
- * @namespace
- */
-jasmine.Clock = {
-  defaultFakeTimer: new jasmine.FakeTimer(),
-
-  reset: function() {
-    jasmine.Clock.assertInstalled();
-    jasmine.Clock.defaultFakeTimer.reset();
-  },
-
-  tick: function(millis) {
-    jasmine.Clock.assertInstalled();
-    jasmine.Clock.defaultFakeTimer.tick(millis);
-  },
-
-  runFunctionsWithinRange: function(oldMillis, nowMillis) {
-    jasmine.Clock.defaultFakeTimer.runFunctionsWithinRange(oldMillis, nowMillis);
-  },
-
-  scheduleFunction: function(timeoutKey, funcToCall, millis, recurring) {
-    jasmine.Clock.defaultFakeTimer.scheduleFunction(timeoutKey, funcToCall, millis, recurring);
-  },
-
-  useMock: function() {
-    if (!jasmine.Clock.isInstalled()) {
-      //TODO: this is using an interface that doesn't exist.
-      var spec = jasmine.getEnv().currentSpec;
-      spec.after(jasmine.Clock.uninstallMock);
-
-      jasmine.Clock.installMock();
-    }
-  },
-
-  installMock: function() {
-    jasmine.Clock.installed = jasmine.Clock.defaultFakeTimer;
-  },
-
-  uninstallMock: function() {
-    jasmine.Clock.assertInstalled();
-    jasmine.Clock.installed = jasmine.Clock.real;
-  },
-
-  real: {
-    setTimeout: jasmine.getGlobal().setTimeout,
-    clearTimeout: jasmine.getGlobal().clearTimeout,
-    setInterval: jasmine.getGlobal().setInterval,
-    clearInterval: jasmine.getGlobal().clearInterval
-  },
-
-  assertInstalled: function() {
-    if (!jasmine.Clock.isInstalled()) {
-      throw new Error("Mock clock is not installed, use jasmine.Clock.useMock()");
-    }
-  },
-
-  isInstalled: function() {
-    return jasmine.Clock.installed == jasmine.Clock.defaultFakeTimer;
-  },
-
-  installed: null
-};
-jasmine.Clock.installed = jasmine.Clock.real;
-
-//else for IE support
-jasmine.getGlobal().setTimeout = function(funcToCall, millis) {
-  if (jasmine.Clock.installed.setTimeout.apply) {
-    return jasmine.Clock.installed.setTimeout.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.setTimeout(funcToCall, millis);
-  }
-};
-
-jasmine.getGlobal().setInterval = function(funcToCall, millis) {
-  if (jasmine.Clock.installed.setInterval.apply) {
-    return jasmine.Clock.installed.setInterval.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.setInterval(funcToCall, millis);
-  }
-};
-
-jasmine.getGlobal().clearTimeout = function(timeoutKey) {
-  if (jasmine.Clock.installed.clearTimeout.apply) {
-    return jasmine.Clock.installed.clearTimeout.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.clearTimeout(timeoutKey);
-  }
-};
-
-jasmine.getGlobal().clearInterval = function(timeoutKey) {
-  if (jasmine.Clock.installed.clearTimeout.apply) {
-    return jasmine.Clock.installed.clearInterval.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.clearInterval(timeoutKey);
-  }
-};
-
 /**
  * @constructor
  */
@@ -2288,6 +2107,201 @@ jasmine.Suite.prototype.execute = function(onComplete) {
     self.finish(onComplete);
   });
 };
+jasmine.Clock = function(global, delayedFunctionScheduler) {
+  var self = this,
+  realTimingFunctions = {
+    setTimeout: global.setTimeout,
+    clearTimeout: global.clearTimeout,
+    setInterval: global.setInterval,
+    clearInterval: global.clearInterval
+  },
+  fakeTimingFunctions = {
+    setTimeout: setTimeout,
+    clearTimeout: clearTimeout,
+    setInterval: setInterval,
+    clearInterval: clearInterval
+  },
+  timer = realTimingFunctions,
+  installed = false;
+
+  self.install = function() {
+    installed = true;
+    timer = fakeTimingFunctions;
+  };
+
+  self.uninstall = function() {
+    delayedFunctionScheduler.reset();
+    installed = false;
+    timer = realTimingFunctions;
+  };
+
+  self.setTimeout = function(fn, delay, params) {
+    if (legacyIE()) {
+      if (arguments.length > 2) {
+        throw new Error("IE < 9 cannot support extra params to setTimeout without a polyfill");
+      }
+      return timer.setTimeout(fn, delay);
+    }
+    return timer.setTimeout.apply(null, arguments);
+  };
+
+  self.setInterval = function(fn, delay, params) {
+    if (legacyIE()) {
+      if (arguments.length > 2) {
+        throw new Error("IE < 9 cannot support extra params to setInterval without a polyfill");
+      }
+      return timer.setInterval(fn, delay);
+    }
+    return timer.setInterval.apply(null, arguments);
+  };
+
+  self.clearTimeout = function(id) {
+    return timer.clearTimeout(id);
+  };
+
+  self.clearInterval = function(id) {
+    return timer.clearInterval(id);
+  };
+
+  self.tick = function(millis) {
+    if (installed) {
+      delayedFunctionScheduler.tick(millis)
+    } else {
+      throw new Error("Mock clock is not installed, use jasmine.Clock.useMock()");
+    }
+  };
+
+  return self;
+
+  function legacyIE() {
+    //if these methods are polyfilled, apply will be present
+    //TODO: it may be difficult to load the polyfill before jasmine loads
+    //(env should be new-ed inside of onload)
+    return !(global.setTimeout || global.setInterval).apply;
+  }
+
+  function setTimeout(fn, delay) {
+    return delayedFunctionScheduler.scheduleFunction(fn, delay, argSlice(arguments,2));
+  }
+
+  function clearTimeout(id) {
+    return delayedFunctionScheduler.removeFunctionWithId(id);
+  }
+
+  function setInterval(fn, interval) {
+    return delayedFunctionScheduler.scheduleFunction(fn, interval, argSlice(arguments, 2), true);
+  }
+
+  function clearInterval(id) {
+    return delayedFunctionScheduler.removeFunctionWithId(id);
+  }
+
+  function argSlice(argsObj, n) {
+    return Array.prototype.slice.call(argsObj, 2);
+  }
+};
+jasmine.DelayedFunctionScheduler = function() {
+  var self = this;
+  var scheduledFunctions = {};
+  var currentTime = 0;
+  var delayedFnCount = 0;
+
+  self.tick = function(millis) {
+    runFunctionsWithinRange(currentTime, currentTime + millis);
+    currentTime = currentTime + millis;
+  };
+
+  self.scheduleFunction = function(funcToCall, millis, params, recurring, timeoutKey, runAtMillis) {
+    timeoutKey = timeoutKey || ++delayedFnCount;
+    runAtMillis = runAtMillis || (currentTime + millis);
+    scheduledFunctions[timeoutKey] = {
+      runAtMillis: runAtMillis,
+      funcToCall: funcToCall,
+      recurring: recurring,
+      params: params,
+      timeoutKey: timeoutKey,
+      millis: millis
+    };
+    return timeoutKey;
+  };
+
+  self.removeFunctionWithId = function(timeoutKey) {
+    delete scheduledFunctions[timeoutKey];
+  };
+
+  self.reset = function() {
+    currentTime = 0;
+    scheduledFunctions = {};
+    delayedFnCount = 0;
+  };
+
+  return self;
+
+
+  //finds/dupes functions within range and removes them.
+  function functionsWithinRange(startMillis, endMillis) {
+    var fnsToRun = [];
+    for (var timeoutKey in scheduledFunctions) {
+      var scheduledFunc = scheduledFunctions[timeoutKey];
+      if (scheduledFunc &&
+          scheduledFunc.runAtMillis >= startMillis &&
+            scheduledFunc.runAtMillis <= endMillis) {
+        //remove fn -- we'll reschedule later if it is recurring.
+        self.removeFunctionWithId(timeoutKey);
+        if (!scheduledFunc.recurring) {
+          fnsToRun.push(scheduledFunc); // schedules each function only once
+        } else {
+          fnsToRun.push(buildNthInstanceOf(scheduledFunc, 0));
+          var additionalTimesFnRunsInRange =
+            Math.floor((endMillis - scheduledFunc.runAtMillis) / scheduledFunc.millis);
+          for (var i = 0; i < additionalTimesFnRunsInRange; i++) {
+            fnsToRun.push(buildNthInstanceOf(scheduledFunc, i + 1));
+          }
+          reschedule(buildNthInstanceOf(scheduledFunc, additionalTimesFnRunsInRange));
+        }
+      }
+    }
+
+    return fnsToRun;
+  }
+
+  function buildNthInstanceOf(scheduledFunc, n) {
+    return {
+      runAtMillis: scheduledFunc.runAtMillis + (scheduledFunc.millis * n),
+      funcToCall: scheduledFunc.funcToCall,
+      params: scheduledFunc.params,
+      millis: scheduledFunc.millis,
+      recurring: scheduledFunc.recurring,
+      timeoutKey: scheduledFunc.timeoutKey
+    };
+  }
+
+  function reschedule(scheduledFn) {
+    self.scheduleFunction(scheduledFn.funcToCall,
+      scheduledFn.millis,
+      scheduledFn.params,
+      true,
+      scheduledFn.timeoutKey,
+      scheduledFn.runAtMillis + scheduledFn.millis);
+  }
+
+
+  function runFunctionsWithinRange(startMillis, endMillis) {
+    var funcsToRun = functionsWithinRange(startMillis, endMillis);
+    if (funcsToRun.length === 0) {
+      return;
+    }
+
+    funcsToRun.sort(function(a, b) {
+      return a.runAtMillis - b.runAtMillis;
+    });
+
+    for (var i = 0; i < funcsToRun.length; ++i) {
+      var funcToRun = funcsToRun[i];
+      funcToRun.funcToCall.apply(null, funcToRun.params);
+    }
+  }
+};
 
 jasmine.version_= {
   "major": 1,
diff --git a/spec/core/ClockSpec.js b/spec/core/ClockSpec.js
new file mode 100644
index 00000000..f5135c31
--- /dev/null
+++ b/spec/core/ClockSpec.js
@@ -0,0 +1,296 @@
+describe("Clock", function() {
+
+// TODO: fullName/SpecFilter is broken, so don't nest describes you want to filter
+
+  it("calls the global setTimeout directly if Clock is not installed", function() {
+    var setTimeout = jasmine.createSpy('setTimeout'),
+      delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['scheduleFunction']),
+      global = { setTimeout: setTimeout },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.setTimeout(delayedFn, 0);
+
+    expect(delayedFunctionScheduler.scheduleFunction).not.toHaveBeenCalled();
+    expect(setTimeout).toHaveBeenCalledWith(delayedFn, 0);
+  });
+
+  it("schedules the delayed function with the fake timer", function() {
+    var setTimeout = jasmine.createSpy('setTimeout'),
+      scheduleFunction = jasmine.createSpy('scheduleFunction'),
+      delayedFunctionScheduler = {scheduleFunction: scheduleFunction},
+      global = { setTimeout: setTimeout },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.install();
+    clock.setTimeout(delayedFn, 0, 'a', 'b');
+
+    expect(setTimeout).not.toHaveBeenCalled();
+    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(delayedFn, 0, ['a', 'b']);
+  });
+
+  it("returns an id for the delayed function", function() {
+    var setTimeout = jasmine.createSpy('setTimeout'),
+      scheduleId = 123,
+      scheduleFunction = jasmine.createSpy('scheduleFunction').andReturn(scheduleId),
+      delayedFunctionScheduler = {scheduleFunction: scheduleFunction},
+      global = { setTimeout: setTimeout },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler),
+      timeoutId;
+
+    clock.install();
+    timeoutId = clock.setTimeout(delayedFn, 0);
+
+    expect(timeoutId).toEqual(123);
+  });
+
+  it("calls the global clearTimeout directly if Clock is not installed", function() {
+    var clearTimeout = jasmine.createSpy('clearTimeout'),
+      delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['clearTimeout']),
+      global = { clearTimeout: clearTimeout },
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.clearTimeout(123);
+
+    expect(clearTimeout).toHaveBeenCalledWith(123);
+  });
+
+  it("clears the scheduled function with the scheduler", function() {
+    var clearTimeout = jasmine.createSpy('clearTimeout'),
+      delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['removeFunctionWithId']),
+      global = { setTimeout: clearTimeout },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.install();
+    clock.clearTimeout(123);
+
+    expect(clearTimeout).not.toHaveBeenCalled();
+    expect(delayedFunctionScheduler.removeFunctionWithId).toHaveBeenCalledWith(123);
+  });
+
+  it("calls the global setInterval directly if Clock is not installed", function() {
+    var setInterval = jasmine.createSpy('setInterval'),
+      delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['scheduleFunction']),
+      global = { setInterval: setInterval },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.setInterval(delayedFn, 0);
+
+    expect(delayedFunctionScheduler.scheduleFunction).not.toHaveBeenCalled();
+    expect(setInterval).toHaveBeenCalledWith(delayedFn, 0);
+  });
+
+  it("schedules the delayed function with the fake timer", function() {
+    var setInterval = jasmine.createSpy('setInterval'),
+      scheduleFunction = jasmine.createSpy('scheduleFunction'),
+      delayedFunctionScheduler = {scheduleFunction: scheduleFunction},
+      global = { setInterval: setInterval },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.install();
+    clock.setInterval(delayedFn, 0, 'a', 'b');
+
+    expect(setInterval).not.toHaveBeenCalled();
+    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(delayedFn, 0, ['a', 'b'], true);
+  });
+
+  it("returns an id for the delayed function", function() {
+    var setInterval = jasmine.createSpy('setInterval'),
+      scheduleId = 123,
+      scheduleFunction = jasmine.createSpy('scheduleFunction').andReturn(scheduleId),
+      delayedFunctionScheduler = {scheduleFunction: scheduleFunction},
+      global = { setInterval: setInterval },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler),
+      intervalId;
+
+    clock.install();
+    intervalId = clock.setInterval(delayedFn, 0);
+
+    expect(intervalId).toEqual(123);
+  });
+
+  it("calls the global clearInterval directly if Clock is not installed", function() {
+    var clearInterval = jasmine.createSpy('clearInterval'),
+      delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['clearInterval']),
+      global = { clearInterval: clearInterval },
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.clearInterval(123);
+
+    expect(clearInterval).toHaveBeenCalledWith(123);
+  });
+
+  it("clears the scheduled function with the scheduler", function() {
+    var clearInterval = jasmine.createSpy('clearInterval'),
+      delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['removeFunctionWithId']),
+      global = { setInterval: clearInterval },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.install();
+    clock.clearInterval(123);
+
+    expect(clearInterval).not.toHaveBeenCalled();
+    expect(delayedFunctionScheduler.removeFunctionWithId).toHaveBeenCalledWith(123);
+  });
+
+  it("gives you a friendly reminder if the Clock is not installed and you tick", function() {
+    var clock = new jasmine.Clock({}, jasmine.createSpyObj('delayedFunctionScheduler', ['tick']));
+    expect(function() {
+      clock.tick(50);
+    }).toThrow();
+  });
+
+  it("can be uninstalled", function() {
+    var setTimeout = jasmine.createSpy('setTimeout'),
+      setInterval = jasmine.createSpy('setInterval'),
+      delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['scheduleFunction', 'tick', 'reset']),
+      global = { setTimeout: setTimeout, setInterval: setInterval },
+      delayedFn = jasmine.createSpy('delayedFn'),
+      clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    clock.install();
+    clock.setTimeout(delayedFn, 0);
+    expect(setTimeout).not.toHaveBeenCalled();
+
+    clock.setInterval(delayedFn, 0);
+    expect(setInterval).not.toHaveBeenCalled();
+
+    expect(function() {
+      clock.tick(0);
+    }).not.toThrow();
+
+    clock.uninstall();
+
+    expect(delayedFunctionScheduler.reset).toHaveBeenCalled();
+
+    clock.setTimeout(delayedFn, 0);
+
+    expect(setTimeout).toHaveBeenCalled();
+
+    clock.setInterval(delayedFn, 0);
+    expect(setInterval).toHaveBeenCalled();
+
+    expect(function() {
+      clock.tick(0);
+    }).toThrow();
+  });
+
+
+  it("on IE < 9, fails if extra args are passed to fake clock", function() {
+    //fail, because this would break in IE9.
+    var setTimeout = jasmine.createSpy('setTimeout'),
+    setInterval = jasmine.createSpy('setInterval'),
+    delayedFunctionScheduler = jasmine.createSpyObj('delayedFunctionScheduler', ['scheduleFunction']),
+    fn = jasmine.createSpy('fn'),
+    global = { setTimeout: setTimeout, setInterval: setInterval },
+    clock = new jasmine.Clock(global, delayedFunctionScheduler);
+
+    setTimeout.apply = null;
+    setInterval.apply = null;
+
+    clock.install();
+
+    clock.setTimeout(fn, 0);
+    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(fn, 0, []);
+    expect(function() {
+      clock.setTimeout(fn, 0, 'extra');
+    }).toThrow();
+
+    clock.setInterval(fn, 0);
+    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(fn, 0, [], true);
+    expect(function() {
+      clock.setInterval(fn, 0, 'extra');
+    }).toThrow();
+  });
+
+});
+
+describe("Clock (acceptance)", function() {
+  it("can run setTimeouts/setIntervals synchronously", function() {
+    var delayedFn1 = jasmine.createSpy('delayedFn1'),
+      delayedFn2 = jasmine.createSpy('delayedFn2'),
+      delayedFn3 = jasmine.createSpy('delayedFn3'),
+      recurring1 = jasmine.createSpy('recurring1'),
+      delayedFunctionScheduler = new jasmine.DelayedFunctionScheduler(),
+      clock = new jasmine.Clock({setTimeout: setTimeout}, delayedFunctionScheduler);
+
+    clock.install();
+
+    clock.setTimeout(delayedFn1, 0, 'some', 'arg');
+    var intervalId = clock.setInterval(recurring1, 50, 'some', 'other', 'args');
+    clock.setTimeout(delayedFn2, 100);
+    clock.setTimeout(delayedFn3, 200);
+
+    expect(delayedFn1).not.toHaveBeenCalled();
+    expect(delayedFn2).not.toHaveBeenCalled();
+    expect(delayedFn3).not.toHaveBeenCalled();
+
+    clock.tick(0);
+
+    expect(delayedFn1).toHaveBeenCalledWith('some', 'arg');
+    expect(delayedFn2).not.toHaveBeenCalled();
+    expect(delayedFn3).not.toHaveBeenCalled();
+
+    clock.tick(50);
+
+    expect(recurring1).toHaveBeenCalledWith('some', 'other', 'args');
+    expect(recurring1.callCount).toBe(1);
+    expect(delayedFn2).not.toHaveBeenCalled();
+    expect(delayedFn3).not.toHaveBeenCalled();
+
+    clock.tick(50);
+
+    expect(recurring1.callCount).toBe(2);
+    expect(delayedFn2).toHaveBeenCalled();
+    expect(delayedFn3).not.toHaveBeenCalled();
+
+    clock.tick(100);
+
+    expect(recurring1.callCount).toBe(4);
+    expect(delayedFn3).toHaveBeenCalled();
+
+    clock.clearInterval(intervalId);
+    clock.tick(50);
+
+    expect(recurring1.callCount).toBe(4);
+  });
+
+  it("can clear a previously set timeout", function() {
+    var clearedFn = jasmine.createSpy('clearedFn'),
+      delayedFunctionScheduler = new jasmine.DelayedFunctionScheduler(),
+      clock = new jasmine.Clock({setTimeout: function() {}}, delayedFunctionScheduler),
+      timeoutId;
+
+    clock.install();
+
+    timeoutId = clock.setTimeout(clearedFn, 100);
+    expect(clearedFn).not.toHaveBeenCalled();
+
+    clock.clearTimeout(timeoutId);
+    clock.tick(100);
+
+    expect(clearedFn).not.toHaveBeenCalled();
+  });
+
+  it("correctly schedules functions after the Clock has advanced", function() {
+    var delayedFn1 = jasmine.createSpy('delayedFn1'),
+      delayedFunctionScheduler = new jasmine.DelayedFunctionScheduler(),
+      clock = new jasmine.Clock({setTimeout: function(){}}, delayedFunctionScheduler);
+
+    clock.install();
+
+    clock.tick(100);
+    clock.setTimeout(delayedFn1, 10, ['some', 'arg']);
+    clock.tick(5);
+    expect(delayedFn1).not.toHaveBeenCalled();
+    clock.tick(5);
+    expect(delayedFn1).toHaveBeenCalled();
+  });
+});
diff --git a/spec/core/DelayedFunctionSchedulerSpec.js b/spec/core/DelayedFunctionSchedulerSpec.js
new file mode 100644
index 00000000..0615f493
--- /dev/null
+++ b/spec/core/DelayedFunctionSchedulerSpec.js
@@ -0,0 +1,142 @@
+describe("DelayedFunctionScheduler", function() {
+  it("schedules a function for later execution", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler(),
+      fn = jasmine.createSpy('fn');
+
+    scheduler.scheduleFunction(fn, 0);
+
+    expect(fn).not.toHaveBeenCalled();
+
+    scheduler.tick(0);
+
+    expect(fn).toHaveBeenCalled();
+  });
+
+  it("optionally passes params to scheduled functions", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler(),
+      fn = jasmine.createSpy('fn');
+
+    scheduler.scheduleFunction(fn, 0, ['foo', 'bar']);
+
+    expect(fn).not.toHaveBeenCalled();
+
+    scheduler.tick(0);
+
+    expect(fn).toHaveBeenCalledWith('foo', 'bar');
+  });
+
+  it("scheduled fns can optionally reoccur", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler(),
+      fn = jasmine.createSpy('fn');
+
+    scheduler.scheduleFunction(fn, 20, [], true);
+
+    expect(fn).not.toHaveBeenCalled();
+
+    scheduler.tick(20);
+
+    expect(fn.callCount).toBe(1);
+
+    scheduler.tick(40);
+
+    expect(fn.callCount).toBe(3);
+
+    scheduler.tick(21);
+
+    expect(fn.callCount).toBe(4);
+
+  });
+
+  it("increments scheduled fns ids unless one is passed", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler();
+
+    expect(scheduler.scheduleFunction(function() {
+    }, 0)).toBe(1);
+    expect(scheduler.scheduleFunction(function() {
+    }, 0)).toBe(2);
+    expect(scheduler.scheduleFunction(function() {
+    }, 0, [], false, 123)).toBe(123);
+    expect(scheduler.scheduleFunction(function() {
+    }, 0)).toBe(3);
+  });
+
+  it("#removeFunctionWithId removes a previously scheduled function with a given id", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler(),
+      fn = jasmine.createSpy('fn'),
+      timeoutKey;
+
+    timeoutKey = scheduler.scheduleFunction(fn, 0);
+
+    expect(fn).not.toHaveBeenCalled();
+
+    scheduler.removeFunctionWithId(timeoutKey);
+
+    scheduler.tick(0);
+
+    expect(fn).not.toHaveBeenCalled();
+  });
+
+  it("reset removes scheduled functions", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler(),
+      fn = jasmine.createSpy('fn');
+
+    scheduler.scheduleFunction(fn, 0);
+
+    expect(fn).not.toHaveBeenCalled();
+
+    scheduler.reset();
+
+    scheduler.tick(0);
+
+    expect(fn).not.toHaveBeenCalled();
+  });
+
+  it("reset resets the returned ids", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler();
+    expect(scheduler.scheduleFunction(function() { }, 0)).toBe(1);
+    expect(scheduler.scheduleFunction(function() { }, 0, [], false, 123)).toBe(123);
+
+    scheduler.reset();
+    expect(scheduler.scheduleFunction(function() { }, 0)).toBe(1);
+    expect(scheduler.scheduleFunction(function() { }, 0, [], false, 123)).toBe(123);
+  });
+
+  it("reset resets the current tick time", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler(),
+      fn = jasmine.createSpy('fn');
+
+    expect(fn).not.toHaveBeenCalled();
+
+    scheduler.tick(15);
+    scheduler.reset();
+
+    scheduler.scheduleFunction(fn, 20, [], false, 1, 20);
+
+    scheduler.tick(5);
+
+    expect(fn).not.toHaveBeenCalled();
+  });
+
+  it("executes recurring functions interleaved with regular functions in the correct order", function() {
+    var scheduler = new jasmine.DelayedFunctionScheduler(),
+      fn = jasmine.createSpy('fn'),
+      recurringCallCount = 0,
+      recurring = jasmine.createSpy('recurring').andCallFake(function() {
+        recurringCallCount++;
+        if (recurringCallCount < 5) {
+          expect(fn).not.toHaveBeenCalled();
+        }
+      });
+
+    scheduler.scheduleFunction(recurring, 10, [], true);
+    scheduler.scheduleFunction(fn, 50);
+
+    scheduler.tick(60);
+
+    expect(recurring).toHaveBeenCalled();
+    expect(recurring.callCount).toBe(6);
+    expect(fn).toHaveBeenCalled();
+  });
+
+});
+
diff --git a/spec/core/EnvSpec.js b/spec/core/EnvSpec.js
index 7211618a..3190a6dd 100644
--- a/spec/core/EnvSpec.js
+++ b/spec/core/EnvSpec.js
@@ -157,3 +157,33 @@ describe("jasmine.Env", function() {
     });
   });
 });
+
+describe("jasmine Env", function() {
+
+  it("Mock clock can be installed and used in tests", function() {
+    var setTimeout = jasmine.createSpy('setTimeout'),
+    globalTimeoutFn = jasmine.createSpy('globalTimeoutFn'),
+    fakeTimeoutFn = jasmine.createSpy('fakeTimeoutFn'),
+    env = new jasmine.Env({global: { setTimeout: setTimeout }});
+
+    env.describe("tests", function() {
+      env.it("test with mock clock", function() {
+        env.clock.install();
+        env.clock.setTimeout(fakeTimeoutFn, 100);
+        env.clock.tick(100);
+      });
+      env.it("test without mock clock", function() {
+        env.clock.setTimeout(globalTimeoutFn, 100);
+      });
+    });
+
+    expect(setTimeout).not.toHaveBeenCalled();
+    expect(fakeTimeoutFn).not.toHaveBeenCalled();
+
+    env.execute();
+
+    expect(fakeTimeoutFn).toHaveBeenCalled();
+    expect(setTimeout).toHaveBeenCalledWith(globalTimeoutFn, 100);
+  });
+
+});
diff --git a/spec/core/MockClockSpec.js b/spec/core/MockClockSpec.js
deleted file mode 100644
index 3aca2621..00000000
--- a/spec/core/MockClockSpec.js
+++ /dev/null
@@ -1,40 +0,0 @@
-//// TODO: Disabling b/c this spec isn't testing what it thinks it is.
-////   Make a proper unit and intergration tests for this object
-//describe("MockClock", function () {
-//
-//  beforeEach(function() {
-//    jasmine.Clock.useMock();
-//  });
-//
-//  describe("setTimeout", function () {
-//    it("should mock the clock when useMock is in a beforeEach", function() {
-//      var expected = false;
-//      setTimeout(function() {
-//        expected = true;
-//      }, 30000);
-//      expect(expected).toBe(false);
-//      jasmine.Clock.tick(30001);
-//      expect(expected).toBe(true);
-//    });
-//  });
-//
-//  describe("setInterval", function () {
-//    it("should mock the clock when useMock is in a beforeEach", function() {
-//      var interval = 0;
-//      setInterval(function() {
-//        interval++;
-//      }, 30000);
-//      expect(interval).toEqual(0);
-//      jasmine.Clock.tick(30001);
-//      expect(interval).toEqual(1);
-//      jasmine.Clock.tick(30001);
-//      expect(interval).toEqual(2);
-//      jasmine.Clock.tick(1);
-//      expect(interval).toEqual(2);
-//    });
-//  });
-//
-//  it("shouldn't complain if you call jasmine.Clock.useMock() more than once", function() {
-//    jasmine.Clock.useMock();
-//  });
-//});
diff --git a/spec/core/RunnerSpec.js b/spec/core/RunnerSpec.js
index 95cd4451..36984a3d 100644
--- a/spec/core/RunnerSpec.js
+++ b/spec/core/RunnerSpec.js
@@ -5,12 +5,6 @@ describe('RunnerTest', function() {
   beforeEach(function() {
     env = new jasmine.Env();
     env.updateInterval = 0;
-
-    fakeTimer = new jasmine.FakeTimer();
-    env.setTimeout = fakeTimer.setTimeout;
-    env.clearTimeout = fakeTimer.clearTimeout;
-    env.setInterval = fakeTimer.setInterval;
-    env.clearInterval = fakeTimer.clearInterval;
   });
 
   describe('beforeEach', function() {
diff --git a/spec/core/SpecRunningSpec.js b/spec/core/SpecRunningSpec.js
index 76841b40..a33efe18 100644
--- a/spec/core/SpecRunningSpec.js
+++ b/spec/core/SpecRunningSpec.js
@@ -5,12 +5,6 @@ describe("jasmine spec running", function () {
   beforeEach(function() {
     env = new jasmine.Env();
     env.updateInterval = 0;
-
-    fakeTimer = new originalJasmine.FakeTimer();
-    env.setTimeout = fakeTimer.setTimeout;
-    env.clearTimeout = fakeTimer.clearTimeout;
-    env.setInterval = fakeTimer.setInterval;
-    env.clearInterval = fakeTimer.clearInterval;
   });
 
   it('should assign spec ids sequentially', function() {
diff --git a/spec/core/SuiteSpec.js b/spec/core/SuiteSpec.js
index 84141dec..36ef4683 100644
--- a/spec/core/SuiteSpec.js
+++ b/spec/core/SuiteSpec.js
@@ -1,16 +1,9 @@
 describe('Suite', function() {
-  var fakeTimer;
   var env;
 
   beforeEach(function() {
     env = new jasmine.Env();
     env.updateInterval = 0;
-
-    fakeTimer = new originalJasmine.FakeTimer();
-    env.setTimeout = fakeTimer.setTimeout;
-    env.clearTimeout = fakeTimer.clearTimeout;
-    env.setInterval = fakeTimer.setInterval;
-    env.clearInterval = fakeTimer.clearInterval;
   });
 
   describe('Specs', function () {
@@ -42,7 +35,7 @@ describe('Suite', function() {
         });
       });
     });
-    
+
     it('#specs should return all immediate children that are specs.', function () {
       var suiteSpecs = suite.specs();
       expect(suiteSpecs.length).toEqual(3);
diff --git a/spec/html/HTMLReporterSpec.js b/spec/html/HTMLReporterSpec.js
index 3eb473fe..69232388 100644
--- a/spec/html/HTMLReporterSpec.js
+++ b/spec/html/HTMLReporterSpec.js
@@ -71,12 +71,6 @@ describe("HtmlReporter", function() {
 
     var runner, spec, fakeTimer;
     beforeEach(function() {
-      fakeTimer = new jasmine.FakeTimer();
-      env.setTimeout = fakeTimer.setTimeout;
-      env.clearTimeout = fakeTimer.clearTimeout;
-      env.setInterval = fakeTimer.setInterval;
-      env.clearInterval = fakeTimer.clearInterval;
-      fakeDocument.location.search = "?";
       env.addReporter(htmlReporter);
     });
 
@@ -89,7 +83,6 @@ describe("HtmlReporter", function() {
         });
 
         env.execute();
-        fakeTimer.tick(0);
 
         var resultEl = getResultMessageDiv(body);
         expect(resultEl.innerHTML).toMatch(/foo/);
diff --git a/spec/jasmine.yml b/spec/jasmine.yml
index 847c9171..134bd2c2 100644
--- a/spec/jasmine.yml
+++ b/spec/jasmine.yml
@@ -11,7 +11,6 @@ src_files:
   - 'core/Env.js'
   - 'core/JsApiReporter.js'
   - 'core/Matchers.js'
-  - 'core/mock-timeout.js'
   - 'core/MultiReporter.js'
   - 'core/NestedResults.js'
   - 'core/PrettyPrinter.js'
diff --git a/spec/node_performance_suite.js b/spec/node_performance_suite.js
new file mode 100644
index 00000000..7797cec4
--- /dev/null
+++ b/spec/node_performance_suite.js
@@ -0,0 +1,176 @@
+var fs = require('fs');
+var util = require('util');
+var path = require('path');
+
+// yes, really keep this here to keep us honest, but only for jasmine's own runner! [xw]
+// undefined = "diz be undefined yo";
+
+
+var jasmineGlobals = require('../lib/jasmine-core/jasmine.js');
+for (var k in jasmineGlobals) {
+  global[k] = jasmineGlobals[k];
+}
+var env = jasmine.getEnv();
+
+var jasmineInterface = {
+  describe: function(description, specDefinitions) {
+    return env.describe(description, specDefinitions);
+  },
+
+  xdescribe: function(description, specDefinitions) {
+    return env.xdescribe(description, specDefinitions);
+  },
+
+  it: function(desc, func) {
+    return env.it(desc, func);
+  },
+
+  xit: function(desc, func) {
+    return env.xit(desc, func);
+  },
+
+  beforeEach: function(beforeEachFunction) {
+    return env.beforeEach(beforeEachFunction);
+  },
+
+  afterEach: function(afterEachFunction) {
+    return env.afterEach(afterEachFunction);
+  },
+
+  expect: function(actual) {
+    return env.expect(actual);
+  },
+
+  addMatchers: function(matchers) {
+    return env.addMatchers(matchers);
+  },
+
+  spyOn: function(obj, methodName) {
+    return env.spyOn(obj, methodName);
+  },
+
+
+  jsApiReporter: new jasmine.JsApiReporter(jasmine)
+};
+
+for (var k in jasmineInterface) {
+  global[k] = jasmineInterface[k];
+}
+
+require('../src/console/ConsoleReporter.js');
+
+/*
+ Pulling in code from jasmine-node.
+
+ We can't just depend on jasmine-node because it has its own jasmine that it uses.
+ */
+
+global.window = {
+  setTimeout: setTimeout,
+  clearTimeout: clearTimeout,
+  setInterval: setInterval,
+  clearInterval: clearInterval
+};
+
+delete global.window;
+
+function noop() {
+}
+
+jasmine.executeSpecs = function(specs, done, isVerbose, showColors) {
+  global.originalJasmine = jasmine;
+
+  for (var i = 0, len = specs.length; i < len; ++i) {
+    var filename = specs[i];
+    require(filename.replace(/\.\w+$/, ""));
+  }
+
+  var jasmineEnv = jasmine.getEnv();
+  var consoleReporter = new jasmine.ConsoleReporter(util.print, done, showColors);
+
+  jasmineEnv.addReporter(consoleReporter);
+  jasmineEnv.execute();
+};
+
+jasmine.getAllSpecFiles = function(dir, matcher) {
+  var specs = [];
+
+  if (fs.statSync(dir).isFile() && dir.match(matcher)) {
+    specs.push(dir);
+  } else {
+    var files = fs.readdirSync(dir);
+    for (var i = 0, len = files.length; i < len; ++i) {
+      var filename = dir + '/' + files[i];
+      if (fs.statSync(filename).isFile() && filename.match(matcher)) {
+        specs.push(filename);
+      } else if (fs.statSync(filename).isDirectory()) {
+        var subfiles = this.getAllSpecFiles(filename, matcher);
+        subfiles.forEach(function(result) {
+          specs.push(result);
+        });
+      }
+    }
+  }
+
+  return specs;
+};
+
+function now() {
+  return new Date().getTime();
+}
+
+jasmine.asyncSpecWait = function() {
+  var wait = jasmine.asyncSpecWait;
+  wait.start = now();
+  wait.done = false;
+  (function innerWait() {
+    waits(10);
+    runs(function() {
+      if (wait.start + wait.timeout < now()) {
+        expect('timeout waiting for spec').toBeNull();
+      } else if (wait.done) {
+        wait.done = false;
+      } else {
+        innerWait();
+      }
+    });
+  })();
+};
+jasmine.asyncSpecWait.timeout = 4 * 1000;
+jasmine.asyncSpecDone = function() {
+  jasmine.asyncSpecWait.done = true;
+};
+
+for (var key in jasmine) {
+  exports[key] = jasmine[key];
+}
+
+/*
+ End jasmine-node runner
+ */
+
+var isVerbose = false;
+var showColors = true;
+process.argv.forEach(function(arg) {
+  switch (arg) {
+    case '--color': showColors = true; break;
+    case '--noColor': showColors = false; break;
+    case '--verbose': isVerbose = true; break;
+  }
+});
+
+var specs = jasmine.getAllSpecFiles(__dirname + '/smoke/', new RegExp("test.js$"));
+var domIndependentSpecs = [];
+for (var i = 0; i < specs.length; i++) {
+  if (fs.readFileSync(specs[i], "utf8").indexOf("document.createElement") < 0) {
+    domIndependentSpecs.push(specs[i]);
+  }
+}
+
+jasmine.executeSpecs(domIndependentSpecs, function(passed) {
+  if (passed) {
+    process.exit(0);
+  } else {
+    process.exit(1);
+  }
+}, isVerbose, showColors);
diff --git a/spec/runner.html b/spec/runner.html
index 79dfa0d6..5df02a83 100644
--- a/spec/runner.html
+++ b/spec/runner.html
@@ -34,7 +34,8 @@
     <script type="text/javascript" src=".././spec/core/ExpectationResultSpec.js"></script>
     <script type="text/javascript" src=".././spec/core/JsApiReporterSpec.js"></script>
     <script type="text/javascript" src=".././spec/core/MatchersSpec.js"></script>
-    <script type="text/javascript" src=".././spec/core/MockClockSpec.js"></script>
+    <script type="text/javascript" src=".././spec/core/ClockSpec.js"></script>
+    <script type="text/javascript" src=".././spec/core/DelayedFunctionSchedulerSpec.js"></script>
     <script type="text/javascript" src=".././spec/core/MultiReporterSpec.js"></script>
     <script type="text/javascript" src=".././spec/core/NestedResultsSpec.js"></script>
     <script type="text/javascript" src=".././spec/core/PrettyPrintSpec.js"></script>
diff --git a/src/core/Clock.js b/src/core/Clock.js
new file mode 100644
index 00000000..47608b89
--- /dev/null
+++ b/src/core/Clock.js
@@ -0,0 +1,93 @@
+jasmine.Clock = function(global, delayedFunctionScheduler) {
+  var self = this,
+  realTimingFunctions = {
+    setTimeout: global.setTimeout,
+    clearTimeout: global.clearTimeout,
+    setInterval: global.setInterval,
+    clearInterval: global.clearInterval
+  },
+  fakeTimingFunctions = {
+    setTimeout: setTimeout,
+    clearTimeout: clearTimeout,
+    setInterval: setInterval,
+    clearInterval: clearInterval
+  },
+  timer = realTimingFunctions,
+  installed = false;
+
+  self.install = function() {
+    installed = true;
+    timer = fakeTimingFunctions;
+  };
+
+  self.uninstall = function() {
+    delayedFunctionScheduler.reset();
+    installed = false;
+    timer = realTimingFunctions;
+  };
+
+  self.setTimeout = function(fn, delay, params) {
+    if (legacyIE()) {
+      if (arguments.length > 2) {
+        throw new Error("IE < 9 cannot support extra params to setTimeout without a polyfill");
+      }
+      return timer.setTimeout(fn, delay);
+    }
+    return timer.setTimeout.apply(null, arguments);
+  };
+
+  self.setInterval = function(fn, delay, params) {
+    if (legacyIE()) {
+      if (arguments.length > 2) {
+        throw new Error("IE < 9 cannot support extra params to setInterval without a polyfill");
+      }
+      return timer.setInterval(fn, delay);
+    }
+    return timer.setInterval.apply(null, arguments);
+  };
+
+  self.clearTimeout = function(id) {
+    return timer.clearTimeout(id);
+  };
+
+  self.clearInterval = function(id) {
+    return timer.clearInterval(id);
+  };
+
+  self.tick = function(millis) {
+    if (installed) {
+      delayedFunctionScheduler.tick(millis)
+    } else {
+      throw new Error("Mock clock is not installed, use jasmine.Clock.useMock()");
+    }
+  };
+
+  return self;
+
+  function legacyIE() {
+    //if these methods are polyfilled, apply will be present
+    //TODO: it may be difficult to load the polyfill before jasmine loads
+    //(env should be new-ed inside of onload)
+    return !(global.setTimeout || global.setInterval).apply;
+  }
+
+  function setTimeout(fn, delay) {
+    return delayedFunctionScheduler.scheduleFunction(fn, delay, argSlice(arguments,2));
+  }
+
+  function clearTimeout(id) {
+    return delayedFunctionScheduler.removeFunctionWithId(id);
+  }
+
+  function setInterval(fn, interval) {
+    return delayedFunctionScheduler.scheduleFunction(fn, interval, argSlice(arguments, 2), true);
+  }
+
+  function clearInterval(id) {
+    return delayedFunctionScheduler.removeFunctionWithId(id);
+  }
+
+  function argSlice(argsObj, n) {
+    return Array.prototype.slice.call(argsObj, 2);
+  }
+};
diff --git a/src/core/DelayedFunctionScheduler.js b/src/core/DelayedFunctionScheduler.js
new file mode 100644
index 00000000..15cb3f37
--- /dev/null
+++ b/src/core/DelayedFunctionScheduler.js
@@ -0,0 +1,102 @@
+jasmine.DelayedFunctionScheduler = function() {
+  var self = this;
+  var scheduledFunctions = {};
+  var currentTime = 0;
+  var delayedFnCount = 0;
+
+  self.tick = function(millis) {
+    runFunctionsWithinRange(currentTime, currentTime + millis);
+    currentTime = currentTime + millis;
+  };
+
+  self.scheduleFunction = function(funcToCall, millis, params, recurring, timeoutKey, runAtMillis) {
+    timeoutKey = timeoutKey || ++delayedFnCount;
+    runAtMillis = runAtMillis || (currentTime + millis);
+    scheduledFunctions[timeoutKey] = {
+      runAtMillis: runAtMillis,
+      funcToCall: funcToCall,
+      recurring: recurring,
+      params: params,
+      timeoutKey: timeoutKey,
+      millis: millis
+    };
+    return timeoutKey;
+  };
+
+  self.removeFunctionWithId = function(timeoutKey) {
+    delete scheduledFunctions[timeoutKey];
+  };
+
+  self.reset = function() {
+    currentTime = 0;
+    scheduledFunctions = {};
+    delayedFnCount = 0;
+  };
+
+  return self;
+
+
+  //finds/dupes functions within range and removes them.
+  function functionsWithinRange(startMillis, endMillis) {
+    var fnsToRun = [];
+    for (var timeoutKey in scheduledFunctions) {
+      var scheduledFunc = scheduledFunctions[timeoutKey];
+      if (scheduledFunc &&
+          scheduledFunc.runAtMillis >= startMillis &&
+            scheduledFunc.runAtMillis <= endMillis) {
+        //remove fn -- we'll reschedule later if it is recurring.
+        self.removeFunctionWithId(timeoutKey);
+        if (!scheduledFunc.recurring) {
+          fnsToRun.push(scheduledFunc); // schedules each function only once
+        } else {
+          fnsToRun.push(buildNthInstanceOf(scheduledFunc, 0));
+          var additionalTimesFnRunsInRange =
+            Math.floor((endMillis - scheduledFunc.runAtMillis) / scheduledFunc.millis);
+          for (var i = 0; i < additionalTimesFnRunsInRange; i++) {
+            fnsToRun.push(buildNthInstanceOf(scheduledFunc, i + 1));
+          }
+          reschedule(buildNthInstanceOf(scheduledFunc, additionalTimesFnRunsInRange));
+        }
+      }
+    }
+
+    return fnsToRun;
+  }
+
+  function buildNthInstanceOf(scheduledFunc, n) {
+    return {
+      runAtMillis: scheduledFunc.runAtMillis + (scheduledFunc.millis * n),
+      funcToCall: scheduledFunc.funcToCall,
+      params: scheduledFunc.params,
+      millis: scheduledFunc.millis,
+      recurring: scheduledFunc.recurring,
+      timeoutKey: scheduledFunc.timeoutKey
+    };
+  }
+
+  function reschedule(scheduledFn) {
+    self.scheduleFunction(scheduledFn.funcToCall,
+      scheduledFn.millis,
+      scheduledFn.params,
+      true,
+      scheduledFn.timeoutKey,
+      scheduledFn.runAtMillis + scheduledFn.millis);
+  }
+
+
+  function runFunctionsWithinRange(startMillis, endMillis) {
+    var funcsToRun = functionsWithinRange(startMillis, endMillis);
+    if (funcsToRun.length === 0) {
+      return;
+    }
+
+    funcsToRun.sort(function(a, b) {
+      return a.runAtMillis - b.runAtMillis;
+    });
+
+    for (var i = 0; i < funcsToRun.length; ++i) {
+      var funcToRun = funcsToRun[i];
+      funcToRun.funcToCall.apply(null, funcToRun.params);
+    }
+  }
+};
diff --git a/src/core/Env.js b/src/core/Env.js
index 52cbf446..15eef30f 100644
--- a/src/core/Env.js
+++ b/src/core/Env.js
@@ -4,12 +4,17 @@
  * @constructor
  */
 (function() {
-  jasmine.Env = function() {
+  jasmine.Env = function(options) {
+    options = options || {};
     var self = this;
+    var global = options.global || jasmine.getGlobal();
+
+    this.clock = new jasmine.Clock(global, new jasmine.DelayedFunctionScheduler());
+
     var suiteConstructor = jasmine.Suite;
     var isSuite = function(thing) {
       return thing instanceof suiteConstructor;
-    }
+    };
     this.jasmine = jasmine;
     this.currentRunner_ = new jasmine.Runner(this, isSuite);
     this.spies_ = [];
@@ -95,8 +100,7 @@
         afterFns: afterFns(suite),
         expectationFactory: expectationFactory,
         exceptionFormatter: exceptionFormatter,
-        //TODO: move spec creation to more appropriate level and remove this shim
-        resultCallback: function(result) { self.currentSpec = null; suite.specComplete(result); },
+        resultCallback: specResultCallback,
         fullNameFactory: function(spec) { return fullNameFactory(spec, suite) },
         startCallback: startCallback,
         description: description,
@@ -110,8 +114,13 @@
       }
 
       return spec;
-    };
 
+      function specResultCallback(result) {
+        self.clock.uninstall();
+        self.currentSpec = null;
+        suite.specComplete(result);
+      }
+    };
 
     var queueConstructor = jasmine.Queue;
     var queueFactory = function() {
@@ -123,12 +132,6 @@
 
   };
 
-
-  jasmine.Env.prototype.setTimeout = jasmine.setTimeout;
-  jasmine.Env.prototype.clearTimeout = jasmine.clearTimeout;
-  jasmine.Env.prototype.setInterval = jasmine.setInterval;
-  jasmine.Env.prototype.clearInterval = jasmine.clearInterval;
-
   //TODO: shim Spec addMatchers behavior into Env. Should be rewritten to remove globals, etc.
   jasmine.Env.prototype.addMatchers = function(matchersPrototype) {
     var parent = this.matchersClass;
diff --git a/src/core/base.js b/src/core/base.js
index 8e411879..255288f1 100644
--- a/src/core/base.js
+++ b/src/core/base.js
@@ -108,8 +108,8 @@ jasmine.MessageResult.prototype.toString = function() {
 /**
  * Getter for the Jasmine environment. Ensures one gets created
  */
-jasmine.getEnv = function() {
-  var env = jasmine.currentEnv_ = jasmine.currentEnv_ || new jasmine.Env();
+jasmine.getEnv = function(options) {
+  var env = jasmine.currentEnv_ = jasmine.currentEnv_ || new jasmine.Env(options);
   //jasmine. singletons in here (setTimeout blah blah).
   return env;
 };
diff --git a/src/core/mock-timeout.js b/src/core/mock-timeout.js
deleted file mode 100644
index bd1251aa..00000000
--- a/src/core/mock-timeout.js
+++ /dev/null
@@ -1,184 +0,0 @@
-// Mock setTimeout, clearTimeout
-// Contributed by Pivotal Computer Systems, www.pivotalsf.com
-
-jasmine.FakeTimer = function() {
-  this.reset();
-
-  var self = this;
-  self.setTimeout = function(funcToCall, millis) {
-    self.timeoutsMade++;
-    self.scheduleFunction(self.timeoutsMade, funcToCall, millis, false);
-    return self.timeoutsMade;
-  };
-
-  self.setInterval = function(funcToCall, millis) {
-    self.timeoutsMade++;
-    self.scheduleFunction(self.timeoutsMade, funcToCall, millis, true);
-    return self.timeoutsMade;
-  };
-
-  self.clearTimeout = function(timeoutKey) {
-    self.scheduledFunctions[timeoutKey] = jasmine.undefined;
-  };
-
-  self.clearInterval = function(timeoutKey) {
-    self.scheduledFunctions[timeoutKey] = jasmine.undefined;
-  };
-
-};
-
-jasmine.FakeTimer.prototype.reset = function() {
-  this.timeoutsMade = 0;
-  this.scheduledFunctions = {};
-  this.nowMillis = 0;
-};
-
-jasmine.FakeTimer.prototype.tick = function(millis) {
-  var oldMillis = this.nowMillis;
-  var newMillis = oldMillis + millis;
-  this.runFunctionsWithinRange(oldMillis, newMillis);
-  this.nowMillis = newMillis;
-};
-
-jasmine.FakeTimer.prototype.runFunctionsWithinRange = function(oldMillis, nowMillis) {
-  var scheduledFunc;
-  var funcsToRun = [];
-  for (var timeoutKey in this.scheduledFunctions) {
-    scheduledFunc = this.scheduledFunctions[timeoutKey];
-    if (scheduledFunc != jasmine.undefined &&
-        scheduledFunc.runAtMillis >= oldMillis &&
-        scheduledFunc.runAtMillis <= nowMillis) {
-      funcsToRun.push(scheduledFunc);
-      this.scheduledFunctions[timeoutKey] = jasmine.undefined;
-    }
-  }
-
-  if (funcsToRun.length > 0) {
-    funcsToRun.sort(function(a, b) {
-      return a.runAtMillis - b.runAtMillis;
-    });
-    for (var i = 0; i < funcsToRun.length; ++i) {
-      try {
-        var funcToRun = funcsToRun[i];
-        this.nowMillis = funcToRun.runAtMillis;
-        funcToRun.funcToCall();
-        if (funcToRun.recurring) {
-          this.scheduleFunction(funcToRun.timeoutKey,
-              funcToRun.funcToCall,
-              funcToRun.millis,
-              true);
-        }
-      } catch(e) {
-      }
-    }
-    this.runFunctionsWithinRange(oldMillis, nowMillis);
-  }
-};
-
-jasmine.FakeTimer.prototype.scheduleFunction = function(timeoutKey, funcToCall, millis, recurring) {
-  this.scheduledFunctions[timeoutKey] = {
-    runAtMillis: this.nowMillis + millis,
-    funcToCall: funcToCall,
-    recurring: recurring,
-    timeoutKey: timeoutKey,
-    millis: millis
-  };
-};
-
-/**
- * @namespace
- */
-jasmine.Clock = {
-  defaultFakeTimer: new jasmine.FakeTimer(),
-
-  reset: function() {
-    jasmine.Clock.assertInstalled();
-    jasmine.Clock.defaultFakeTimer.reset();
-  },
-
-  tick: function(millis) {
-    jasmine.Clock.assertInstalled();
-    jasmine.Clock.defaultFakeTimer.tick(millis);
-  },
-
-  runFunctionsWithinRange: function(oldMillis, nowMillis) {
-    jasmine.Clock.defaultFakeTimer.runFunctionsWithinRange(oldMillis, nowMillis);
-  },
-
-  scheduleFunction: function(timeoutKey, funcToCall, millis, recurring) {
-    jasmine.Clock.defaultFakeTimer.scheduleFunction(timeoutKey, funcToCall, millis, recurring);
-  },
-
-  useMock: function() {
-    if (!jasmine.Clock.isInstalled()) {
-      //TODO: this is using an interface that doesn't exist.
-      var spec = jasmine.getEnv().currentSpec;
-      spec.after(jasmine.Clock.uninstallMock);
-
-      jasmine.Clock.installMock();
-    }
-  },
-
-  installMock: function() {
-    jasmine.Clock.installed = jasmine.Clock.defaultFakeTimer;
-  },
-
-  uninstallMock: function() {
-    jasmine.Clock.assertInstalled();
-    jasmine.Clock.installed = jasmine.Clock.real;
-  },
-
-  real: {
-    setTimeout: jasmine.getGlobal().setTimeout,
-    clearTimeout: jasmine.getGlobal().clearTimeout,
-    setInterval: jasmine.getGlobal().setInterval,
-    clearInterval: jasmine.getGlobal().clearInterval
-  },
-
-  assertInstalled: function() {
-    if (!jasmine.Clock.isInstalled()) {
-      throw new Error("Mock clock is not installed, use jasmine.Clock.useMock()");
-    }
-  },
-
-  isInstalled: function() {
-    return jasmine.Clock.installed == jasmine.Clock.defaultFakeTimer;
-  },
-
-  installed: null
-};
-jasmine.Clock.installed = jasmine.Clock.real;
-
-//else for IE support
-jasmine.getGlobal().setTimeout = function(funcToCall, millis) {
-  if (jasmine.Clock.installed.setTimeout.apply) {
-    return jasmine.Clock.installed.setTimeout.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.setTimeout(funcToCall, millis);
-  }
-};
-
-jasmine.getGlobal().setInterval = function(funcToCall, millis) {
-  if (jasmine.Clock.installed.setInterval.apply) {
-    return jasmine.Clock.installed.setInterval.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.setInterval(funcToCall, millis);
-  }
-};
-
-jasmine.getGlobal().clearTimeout = function(timeoutKey) {
-  if (jasmine.Clock.installed.clearTimeout.apply) {
-    return jasmine.Clock.installed.clearTimeout.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.clearTimeout(timeoutKey);
-  }
-};
-
-jasmine.getGlobal().clearInterval = function(timeoutKey) {
-  if (jasmine.Clock.installed.clearTimeout.apply) {
-    return jasmine.Clock.installed.clearInterval.apply(this, arguments);
-  } else {
-    return jasmine.Clock.installed.clearInterval(timeoutKey);
-  }
-};
-
diff --git a/tasks/jasmine_dev/sources.rb b/tasks/jasmine_dev/sources.rb
index 06b65c10..dfd3e611 100644
--- a/tasks/jasmine_dev/sources.rb
+++ b/tasks/jasmine_dev/sources.rb
@@ -8,7 +8,6 @@ class JasmineDev < Thor
       "Reporter.js",
       "JsApiReporter.js",
       "Matchers.js",
-      "mock-timeout.js",
       "MultiReporter.js",
       "NestedResults.js",
       "PrettyPrinter.js",
@@ -16,6 +15,8 @@ class JasmineDev < Thor
       "Runner.js",
       "Spec.js",
       "Suite.js",
+      "Clock.js",
+      "DelayedFunctionScheduler.js"
     ],
 
     :html => [