diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_5/Object/regress-465476.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_5/Object/regress-465476.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,63 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 465476;
+var summary = '"-0" and "0" are distinct properties.';
+var actual = '';
+var expect = '';
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+ 
+  var x = { "0": 3, "-0": 7 };
+
+  expect = actual = 'No Exception';
+
+  try
+  {
+    if (!("0" in x))
+      throw "0 not in x";
+    if (!("-0" in x))
+      throw "-0 not in x";
+    delete x[0];
+    if ("0" in x)
+      throw "0 in x after delete";
+    if (!("-0" in x))
+      throw "-0 removed from x after unassociated delete";
+    delete x["-0"];
+    if ("-0" in x)
+      throw "-0 in x after delete";
+    x[0] = 3;
+    if (!("0" in x))
+      throw "0 not in x after insertion of 0 property";
+    if ("-0" in x)
+      throw "-0 in x after insertion of 0 property";
+    x["-0"] = 7;
+    if (!("-0" in x))
+      throw "-0 not in x after reinsertion";
+
+    var props = [];
+    for (var i in x)
+      props.push(i);
+    if (props.length !== 2)
+      throw "not all props found!";
+  }
+  catch(ex)
+  {
+    actual = ex + '';
+  }
+  reportCompare(expect, actual, summary);
+
+  exitFunc ('test');
+}