Index: core.js
===================================================================
--- core.js	(revision 6533)
+++ core.js	(working copy)
@@ -409,12 +409,12 @@
 	},
 
 	inArray: function( elem, array ) {
+		if(array.indexOf) return array.indexOf(elem);
 		for ( var i = 0, length = array.length; i < length; i++ ) {
 			if ( array[ i ] === elem ) {
 				return i;
 			}
 		}
-
 		return -1;
 	},