diff --git a/CHANGELOG b/CHANGELOG
index ac6289a..4c903da 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Make sure event handlers and their wrappers are removed from the cache by Event.stopObserving.  [sam, Severin Heiniger]
+
 * Add line numbers to failures when unit testing in Firefox.  Closes #9231.  [John Resig]
 
 * Fix Function#argumentNames for Opera and IE.  [Thomas Fuchs]
diff --git a/src/event.js b/src/event.js
index cb13b3d..850772d 100644
--- a/src/event.js
+++ b/src/event.js
@@ -24,6 +24,8 @@ Object.extend(Event, {
               'DOMSubtreeModified', 'DOMNodeInserted', 
               'NodeInsertedIntoDocument', 'DOMAttrModified', 
               'DOMCharacterDataModified'],
+              
+  cache: { },
 
   relatedTarget: function(event) {
     var element;
@@ -106,7 +108,7 @@ Event.extend = (function() {
 })();
 
 Object.extend(Event, (function() {
-  var cache = { };
+  var cache = Event.cache;
   
   function getEventID(element) {
     if (element._eventID) return element._eventID;
@@ -151,9 +153,9 @@ Object.extend(Event, (function() {
   }
   
   function destroyWrapper(id, eventName, handler) {
-    var c = getCacheForID(id), name = getDOMEventName(eventName);
-    if (!c[name]) return false;
-    c[name] = c[name].without(findWrapper(id, eventName, handler));
+    var c = getCacheForID(id);
+    if (!c[eventName]) return false;
+    c[eventName] = c[eventName].without(findWrapper(id, eventName, handler));
   }
   
   function destroyCache() {
@@ -204,6 +206,8 @@ Object.extend(Event, (function() {
       } else {
         element.detachEvent("on" + name, wrapper);
       }
+      
+      destroyWrapper(id, eventName, handler);
     },
   
     fire: function(element, eventName, memo) {
diff --git a/test/unit/event.html b/test/unit/event.html
index 3e08aca..049495c 100644
--- a/test/unit/event.html
+++ b/test/unit/event.html
@@ -166,6 +166,22 @@
       assertEqual(1, count);
     }},
     
+    testStopObservingRemovesHandlerFromCache: function() { with(this) {
+      var span = $("span"), observer = function() { }, eventID;
+      
+      span.observe("somethingHappened", observer);
+      eventID = span._eventID;
+      
+      assert(Event.cache[eventID]);
+      assert(Object.isArray(Event.cache[eventID].somethingHappened));
+      assertEqual(1, Event.cache[eventID].somethingHappened.length);
+      
+      span.stopObserving("somethingHappened", observer);
+      assert(Event.cache[eventID]);
+      assert(Object.isArray(Event.cache[eventID].somethingHappened));
+      assertEqual(0, Event.cache[eventID].somethingHappened.length);
+    }},
+    
     testDocumentContentLoadedEventFiresBeforeWindowLoad: function() { with(this) {
       assert(eventResults.contentLoaded, "contentLoaded");
       assert(eventResults.contentLoaded.endOfDocument, "contentLoaded.endOfDocument");