--- ./framework/impl/src/main/javascript/prototype/patches.js	2008-07-11 01:13:19.000000000 +0200
+++ ./framework/impl/src/main/javascript/prototype/patches.js	2008-08-07 20:38:49.000000000 +0200
@@ -72,13 +72,16 @@
 	        	var wrappers = cache[eventName];
 	        	var domEventName = Event.getDOMEventName(eventName);
 	        	
-	        	wrappers.each(function(wrapper) {
-					if (node.removeEventListener) {
-						node.removeEventListener(domEventName, wrapper, false);
-					} else {
-						node.detachEvent("on" + domEventName, wrapper);
-					}
-	            });            	
+                // NXP-2587: make sure wrappers is not null
+                if (wrappers) {
+    	        	wrappers.each(function(wrapper) {
+    					if (node.removeEventListener) {
+    						node.removeEventListener(domEventName, wrapper, false);
+    					} else {
+    						node.detachEvent("on" + domEventName, wrapper);
+    					}
+    	            });            	
+                }
 	    		
 	            cache[eventName] = null;
 	        }