diff -r 000000000000 -r 6474c204b198 js/src/tests/test262/ch11/11.4/11.4.1/11.4.1-4.a-4.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/test262/ch11/11.4/11.4.1/11.4.1-4.a-4.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,22 @@
+/// Copyright (c) 2012 Ecma International.  All rights reserved. 
+/// Ecma International makes this code available under the terms and conditions set
+/// forth on http://hg.ecmascript.org/tests/test262/raw-file/tip/LICENSE (the 
+/// "Use Terms").   Any redistribution of this code must retain the above 
+/// copyright and this notice and otherwise comply with the Use Terms.
+/**
+ * This test is actually testing the [[Delete]] internal method (8.12.8). Since the
+ * language provides no way to directly exercise [[Delete]], the tests are placed here.
+ *
+ * @path ch11/11.4/11.4.1/11.4.1-4.a-4.js
+ * @description delete operator returns false when deleting a non-configurable data property (NaN)
+ */
+
+
+function testcase() {
+  // NaN (15.1.1.1) has [[Configurable]] set to false.
+  var d = delete NaN;
+  if (d === false) {
+    return true;
+  }
+ }
+runTestCase(testcase);