diff --git a/src/core.js b/src/core.js
index d4a0e61b..6e1f7452 100644
--- a/src/core.js
+++ b/src/core.js
@@ -441,7 +441,7 @@ jQuery.extend({
 		return jQuery.type(obj) === "function";
 	},
 
-	isArray: function( obj ) {
+	isArray: Array.isArray || function( obj ) {
 		return jQuery.type(obj) === "array";
 	},