fixing a few more memory leaks in IE

src/offset.js

@@ -75,6 +75,8 @@ jQuery.offset = {
 
 		body.removeChild( container );
 		jQuery.offset.initialize = function(){};
+		
+		body = container = innerDiv = checkDiv = table = td = null;
 	},
 
 	bodyOffset: function(body) {

src/support.js

@@ -88,10 +88,11 @@
 		document.body.appendChild( div );
 		jQuery.boxModel = jQuery.support.boxModel = div.offsetWidth === 2;
 		document.body.removeChild( div ).style.display = 'none';
+		div = null;
 	});
 
 	// release memory in IE
-	div = null;
+	root = script = div = all = a = null;
 })();
 
 jQuery.props = {