No need to use the conditional comment for binding the onunload event in IE.

diff --git a/src/event.js b/src/event.js
index b50a1ec..a2b512a 100644 (file)
--- a/src/event.js
+++ b/src/event.js
@@ -882,15 +882,15 @@ jQuery.each( ("blur focus load resize scroll unload click dblclick " +
 // Window isn't included so as not to unbind existing unload events
 // More info:
 //  - http://isaacschlueter.com/2006/10/msie-memory-leaks/
-/*@cc_on
-window.attachEvent("onunload", function() {
-       for ( var id in jQuery.cache ) {
-               if ( jQuery.cache[ id ].handle ) {
-                       // Try/Catch is to handle iframes being unloaded, see #4280
-                       try {
-                               jQuery.event.remove( jQuery.cache[ id ].handle.elem );
-                       } catch(e) {}
+if ( window.attachEvent ) {
+       window.attachEvent("onunload", function() {
+               for ( var id in jQuery.cache ) {
+                       if ( jQuery.cache[ id ].handle ) {
+                               // Try/Catch is to handle iframes being unloaded, see #4280
+                               try {
+                                       jQuery.event.remove( jQuery.cache[ id ].handle.elem );
+                               } catch(e) {}
+                       }
                }
-       }
-});
-@*/
+       });
+}