diff -r 000000000000 -r 6474c204b198 js/src/tests/test262/ch11/11.3/11.3.1/S11.3.1_A4_T5.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/test262/ch11/11.3/11.3.1/S11.3.1_A4_T5.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,24 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/**
+ * Operator x++ returns ToNumber(x)
+ *
+ * @path ch11/11.3/11.3.1/S11.3.1_A4_T5.js
+ * @description Type(x) is Object object or Function object
+ */
+
+//CHECK#1
+var x = {}; 
+var y = x++;
+if (isNaN(y) !== true) {
+  $ERROR('#1: var x = {}; var y = x++; y === Not-a-Number. Actual: ' + (y));
+}
+
+//CHECK#2
+var x = function(){return 1}; 
+var y = x++;
+if (isNaN(y) !== true) {
+  $ERROR('#2: var x = function(){return 1}; var y = x++; y === Not-a-Number. Actual: ' + (y));
+}
+