diff -r 000000000000 -r 6474c204b198 modules/libjar/test/unit/test_bug637286.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/modules/libjar/test/unit/test_bug637286.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,27 @@
+/* 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/. */
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+
+// Check that the zip cache can expire entries from nested jars
+var ios = Cc["@mozilla.org/network/io-service;1"].
+          getService(Ci.nsIIOService);
+
+function open_inner_zip(base, idx) {
+    var spec = "jar:" + base + "inner" + idx + ".zip!/foo";
+    var channel = ios.newChannel(spec, null, null);
+    var stream = channel.open();
+}
+
+function run_test() {
+  var file = do_get_file("data/test_bug637286.zip");
+  var outerJarBase = "jar:" + ios.newFileURI(file).spec + "!/";
+
+  for (var i = 0; i < 40; i++) {
+    open_inner_zip(outerJarBase, i);
+    gc();
+  }
+}
+