diff --git a/lib/args.js b/lib/args.js
index cc4c0f3..896955c 100644
--- a/lib/args.js
+++ b/lib/args.js
@@ -1,7 +1,8 @@
 /*jshint node:true */
 define([
-	'dojo/_base/array'
-], function (array) {
+	'dojo/_base/array',
+	'dojo/_base/lang'
+], function (array, lang) {
 	var rawArgs,
 
 		/**
@@ -44,7 +45,7 @@ define([
 
 		// Support multiple arguments with the same name
 		if (arg[0] in args) {
-			if (!Array.isArray(args[arg[0]])) {
+			if (!lang.isArray(args[arg[0]])) {
 				args[arg[0]] = [ args[arg[0]] ];
 			}