diff --git a/dom/workers/Events.cpp b/dom/workers/Events.cpp
index d2884a88ad3..a28a1df91aa 100644
--- a/dom/workers/Events.cpp
+++ b/dom/workers/Events.cpp
@@ -75,6 +75,7 @@ class Event : public PrivatizableBase
 
 protected:
   bool mStopPropagationCalled;
+  bool mStopImmediatePropagationCalled;
 
 public:
   static bool
@@ -168,9 +169,16 @@ public:
     return JSVAL_TO_BOOLEAN(canceled);
   }
 
+  static bool
+  ImmediatePropagationStopped(JSContext* aCx, JSObject* aEvent)
+  {
+    Event* event = GetPrivate(aCx, aEvent);
+    return event ? event->mStopImmediatePropagationCalled : false;
+  }
+
 protected:
   Event()
-  : mStopPropagationCalled(false)
+  : mStopPropagationCalled(false), mStopImmediatePropagationCalled(false)
   {
     MOZ_COUNT_CTOR(mozilla::dom::workers::Event);
   }
@@ -230,6 +238,7 @@ protected:
                   bool aIsTrusted)
   {
     aEvent->mStopPropagationCalled = false;
+    aEvent->mStopImmediatePropagationCalled = false;
 
     jsval now;
     if (!JS_NewNumberValue(aCx, JS_Now(), &now)) {
@@ -319,6 +328,21 @@ private:
     return true;
   }
 
+  static JSBool
+  StopImmediatePropagation(JSContext* aCx, uintN aArgc, jsval* aVp)
+  {
+    JSObject* obj = JS_THIS_OBJECT(aCx, aVp);
+
+    Event* event = GetInstancePrivate(aCx, obj, sFunctions[3].name);
+    if (!event) {
+      return false;
+    }
+
+    event->mStopImmediatePropagationCalled = true;
+
+    return true;
+  }
+  
   static JSBool
   PreventDefault(JSContext* aCx, uintN aArgc, jsval* aVp)
   {
@@ -399,6 +423,7 @@ JSFunctionSpec Event::sFunctions[] = {
   JS_FN("stopPropagation", StopPropagation, 0, FUNCTION_FLAGS),
   JS_FN("preventDefault", PreventDefault, 0, FUNCTION_FLAGS),
   JS_FN("initEvent", InitEvent, 3, FUNCTION_FLAGS),
+  JS_FN("stopImmediatePropagation", StopImmediatePropagation, 0, FUNCTION_FLAGS),
   JS_FS_END
 };
 
@@ -1115,6 +1140,12 @@ EventWasCanceled(JSContext* aCx, JSObject* aEvent)
   return Event::WasCanceled(aCx, aEvent);
 }
 
+bool
+EventImmediatePropagationStopped(JSContext* aCx, JSObject* aEvent)
+{
+  return Event::ImmediatePropagationStopped(aCx, aEvent);
+}
+
 bool
 DispatchEventToTarget(JSContext* aCx, JSObject* aTarget, JSObject* aEvent,
                       bool* aPreventDefaultCalled)
diff --git a/dom/workers/Events.h b/dom/workers/Events.h
index cb5ad2a6bb6..f71e6e50f91 100644
--- a/dom/workers/Events.h
+++ b/dom/workers/Events.h
@@ -80,6 +80,9 @@ SetEventTarget(JSContext* aCx, JSObject* aEvent, JSObject* aTarget);
 bool
 EventWasCanceled(JSContext* aCx, JSObject* aEvent);
 
+bool
+EventImmediatePropagationStopped(JSContext* aCx, JSObject* aEvent);
+
 bool
 DispatchEventToTarget(JSContext* aCx, JSObject* aTarget, JSObject* aEvent,
                       bool* aPreventDefaultCalled);
diff --git a/dom/workers/ListenerManager.cpp b/dom/workers/ListenerManager.cpp
index 3f7da2bb573..79ee053ab10 100644
--- a/dom/workers/ListenerManager.cpp
+++ b/dom/workers/ListenerManager.cpp
@@ -392,6 +392,10 @@ ListenerManager::DispatchEvent(JSContext* aCx, JSObject* aTarget,
   }
 
   for (size_t index = 0; index < listeners.length(); index++) {
+    if (events::EventImmediatePropagationStopped(aCx, aEvent)) {
+      break;
+    }
+
     // If anything fails in here we want to report the exception and continue on
     // to the next listener rather than bailing out. If something fails and
     // does not set an exception then we bail out entirely as we've either run
diff --git a/dom/workers/test/eventDispatch_worker.js b/dom/workers/test/eventDispatch_worker.js
index 586eeb95e65..1b633f67248 100644
--- a/dom/workers/test/eventDispatch_worker.js
+++ b/dom/workers/test/eventDispatch_worker.js
@@ -22,9 +22,14 @@ addEventListener(fakeEventType, function(event) {
   if (event.isTrusted) {
     throw new Error("Event should be untrusted!");
   }
+  event.stopImmediatePropagation();
   postMessage(event.data);
 }, false, true);
 
+addEventListener(fakeEventType, function(event) {
+  throw new Error("This shouldn't get called because of stopImmediatePropagation.");
+}, false, true);
+
 var count = 0;
 onmessage = function(event) {
   if (event.target !== self || event.currentTarget !== self) {