diff --git a/js/tests/js1_8/extensions/regress-446169-01.js b/js/tests/js1_8/extensions/regress-446169-01.js
new file mode 100755
index 000000000000..a120ebf8cb25
--- /dev/null
+++ b/js/tests/js1_8/extensions/regress-446169-01.js
@@ -0,0 +1,82 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is JavaScript Engine testing utilities.
+ *
+ * The Initial Developer of the Original Code is
+ * Mozilla Foundation.
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s): romaxa
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+var gTestfile = 'regress-446169-01.js';
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 446169;
+var summary = 'Do not assert: Thin_GetWait(tl->owner) in thread-safe build';
+var actual = 'No Crash';
+var expect = 'No Crash';
+
+var array = [{}, {}, {}, {}];
+
+function foo() 
+{
+  for (var i = 0; i != 42*42*42; ++i) 
+  {
+    var obj = array[i % array.length];
+    obj["a"+i] = 1;
+    var tmp = {};
+    tmp["a"+i] = 2;
+  }
+}
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+ 
+  if (typeof scatter == 'function')
+  {
+    scatter([foo, foo, foo, foo]);
+  }
+  else
+  {
+    print('Test skipped. Requires thread-safe build with scatter function.');
+  }
+  reportCompare(expect, actual, summary);
+
+  exitFunc ('test');
+}
+
+
diff --git a/js/tests/js1_8/extensions/regress-446169-02.js b/js/tests/js1_8/extensions/regress-446169-02.js
new file mode 100755
index 000000000000..6f3fc5672254
--- /dev/null
+++ b/js/tests/js1_8/extensions/regress-446169-02.js
@@ -0,0 +1,80 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is JavaScript Engine testing utilities.
+ *
+ * The Initial Developer of the Original Code is
+ * Mozilla Foundation.
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s): Igor Bukanov
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+var gTestfile = 'regress-446169-02.js';
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 446169;
+var summary = 'Do not assert: Thin_GetWait(tl->owner) in thread-safe build';
+var actual = 'No Crash';
+var expect = 'No Crash';
+
+var array = [];
+for (var i = 0; i != 100*1000; i += 2) {
+    array[i] = i;
+    array[i+1] = i;
+}
+
+var src = array.join(';x');
+
+function f() {
+    new Function(src);
+}
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  enterFunc ('test');
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+ 
+  if (typeof scatter == 'function')
+  {
+    scatter([f, f, f, f]);
+  }
+  else
+  {
+    print('Test skipped. Requires thread-safe build with scatter function.');
+  }
+  reportCompare(expect, actual, summary);
+
+  exitFunc ('test');
+}
+
+