Index: core.js
===================================================================
--- core.js	(revision 5143)
+++ core.js	(working copy)
@@ -661,6 +661,12 @@
 	
 	cache: {},
 	
+	proxy: function( fn, proxy ){
+		// Set the guid of unique handler to the same of original handler, so it can be removed 
+		proxy.guid = fn.guid = fn.guid || jQuery.event.guid++;
+		return proxy;//so proxy can be declared as an argument
+	},
+	
 	data: function( elem, name, data ) {
 		elem = elem == window ?
 			windowData :
Index: event.js
===================================================================
--- event.js	(revision 5143)
+++ event.js	(working copy)
@@ -26,16 +26,13 @@
 			var fn = handler; 
 
 			// Create unique handler function, wrapped around original handler 
-			handler = function() { 
+			handler = jQuery.proxy( fn, function() { 
 				// Pass arguments and context to original handler 
 				return fn.apply(this, arguments); 
-			};
+			});
 
 			// Store data in unique handler 
 			handler.data = data;
-
-			// Set the guid of unique handler to the same of original handler, so it can be removed 
-			handler.guid = fn.guid;
 		}
 
 		// Init the element's event structure
@@ -401,11 +398,12 @@
 	},
 	
 	one: function( type, data, fn ) {
+		var one = jQuery.proxy( fn || data, function(event) {
+			jQuery(this).unbind(event, one);
+			return (fn || data).apply( this, arguments);
+		});
 		return this.each(function(){
-			jQuery.event.add( this, type, function(event) {
-				jQuery(this).unbind(event);
-				return (fn || data).apply( this, arguments);
-			}, fn && data);
+			jQuery.event.add( this, type, one, fn && data);
 		});
 	},