diff --git a/layout/Makefile.in b/layout/Makefile.in
index 01ef2692b0d5..f8fc5554f7cb 100644
--- a/layout/Makefile.in
+++ b/layout/Makefile.in
@@ -70,6 +70,7 @@ DIRS           += build
 
 ifdef ENABLE_TESTS
 PARALLEL_DIRS += \
+  mathml/tests \
   xul/test \
   xul/base/test \
   $(NULL)
diff --git a/layout/mathml/nsMathMLmactionFrame.cpp b/layout/mathml/nsMathMLmactionFrame.cpp
index a2f18416f301..94e3de745063 100644
--- a/layout/mathml/nsMathMLmactionFrame.cpp
+++ b/layout/mathml/nsMathMLmactionFrame.cpp
@@ -84,12 +84,12 @@ nsMathMLmactionFrame::~nsMathMLmactionFrame()
   // unregister us as a mouse event listener ...
   //  printf("maction:%p unregistering as mouse event listener ...\n", this);
   if (mListener) {
-    mContent->RemoveEventListener(NS_LITERAL_STRING("click"), mListener,
-                                  false);
-    mContent->RemoveEventListener(NS_LITERAL_STRING("mouseover"), mListener,
-                                  false);
-    mContent->RemoveEventListener(NS_LITERAL_STRING("mouseout"), mListener,
-                                  false);
+    mContent->RemoveSystemEventListener(NS_LITERAL_STRING("click"), mListener,
+                                        false);
+    mContent->RemoveSystemEventListener(NS_LITERAL_STRING("mouseover"), mListener,
+                                        false);
+    mContent->RemoveSystemEventListener(NS_LITERAL_STRING("mouseout"), mListener,
+                                        false);
   }
 }
 
@@ -228,12 +228,12 @@ nsMathMLmactionFrame::SetInitialChildList(ChildListID     aListID,
     // create mouse event listener and register it
     mListener = new nsMathMLmactionFrame::MouseListener(this);
     // printf("maction:%p registering as mouse event listener ...\n", this);
-    mContent->AddEventListener(NS_LITERAL_STRING("click"), mListener,
-                               false, false);
-    mContent->AddEventListener(NS_LITERAL_STRING("mouseover"), mListener,
-                               false, false);
-    mContent->AddEventListener(NS_LITERAL_STRING("mouseout"), mListener,
-                               false, false);
+    mContent->AddSystemEventListener(NS_LITERAL_STRING("click"), mListener,
+                                     false, false);
+    mContent->AddSystemEventListener(NS_LITERAL_STRING("mouseover"), mListener,
+                                     false, false);
+    mContent->AddSystemEventListener(NS_LITERAL_STRING("mouseout"), mListener,
+                                     false, false);
   }
   return rv;
 }
diff --git a/layout/mathml/tests/Makefile.in b/layout/mathml/tests/Makefile.in
new file mode 100644
index 000000000000..fd34d64d43b7
--- /dev/null
+++ b/layout/mathml/tests/Makefile.in
@@ -0,0 +1,52 @@
+#
+# ***** 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 mozilla.org code.
+#
+# The Initial Developer of the Original Code is
+# Mozilla Foundation.
+# Portions created by the Initial Developer are Copyright (C) 2011
+# the Initial Developer. All Rights Reserved.
+#
+# Contributor(s):
+#
+# Alternatively, the contents of this file may be used under the terms of
+# either of 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 *****
+
+DEPTH		= ../../..
+topsrcdir	= @top_srcdir@
+srcdir		= @srcdir@
+VPATH		= @srcdir@
+relativesrcdir  = layout/mathml/tests
+
+include $(DEPTH)/config/autoconf.mk
+include $(topsrcdir)/config/rules.mk
+
+_TEST_FILES =\
+	test_bug706406.html \
+	$(NULL)
+
+libs:: $(_TEST_FILES)
+	$(INSTALL) $(foreach f,$^,"$f") $(DEPTH)/_tests/testing/mochitest/tests/$(relativesrcdir)
diff --git a/layout/mathml/tests/test_bug706406.html b/layout/mathml/tests/test_bug706406.html
new file mode 100644
index 000000000000..76cfc6352656
--- /dev/null
+++ b/layout/mathml/tests/test_bug706406.html
@@ -0,0 +1,71 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=706406
+-->
+<head>
+  <title>Test for Bug 706406</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="application/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=706406">Mozilla Bug 706406</a>
+<p id="display"></p>
+<math xmlns="http://www.w3.org/1998/Math/MathML">
+  <maction actiontype="toggle" id="maction">
+    <mn>1</mn>
+    <mn>2</mn>
+  </maction>
+</math>
+<pre id="test">
+<script type="application/javascript">
+
+/** Test for Bug 706406 **/
+
+function doTest()
+{
+  function doStopPropagation(aEvent) {
+    aEvent.stopPropagation();
+  }
+
+  var maction = document.getElementById("maction");
+
+  synthesizeMouseAtCenter(maction, {});
+
+  is(maction.getAttribute("selection"), "2",
+     "maction's selection attribute isn't 2 by first click");
+
+  synthesizeMouseAtCenter(maction, {});
+
+  is(maction.getAttribute("selection"), "1",
+     "maction's selection attribute isn't 1 by second click");
+
+  window.addEventListener("mousedown", doStopPropagation, true);
+  window.addEventListener("mouseup", doStopPropagation, true);
+  window.addEventListener("click", doStopPropagation, true);
+
+  synthesizeMouseAtCenter(maction, {});
+
+  is(maction.getAttribute("selection"), "2",
+     "maction's selection attribute isn't 2 by first click called stopPropagation()");
+
+  synthesizeMouseAtCenter(maction, {});
+
+  is(maction.getAttribute("selection"), "1",
+     "maction's selection attribute isn't 1 by second click called stopPropagation()");
+
+  window.removeEventListener("mousedown", doStopPropagation, true);
+  window.removeEventListener("mouseup", doStopPropagation, true);
+  window.removeEventListener("click", doStopPropagation, true);
+
+  SimpleTest.finish();
+}
+
+SimpleTest.waitForExplicitFinish();
+SimpleTest.waitForFocus(doTest);
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/toolkit-makefiles.sh b/toolkit/toolkit-makefiles.sh
index f86f520fc8d4..d1d0edb0d44c 100644
--- a/toolkit/toolkit-makefiles.sh
+++ b/toolkit/toolkit-makefiles.sh
@@ -824,6 +824,7 @@ if [ "$ENABLE_TESTS" ]; then
     layout/generic/test/Makefile
     layout/inspector/tests/Makefile
     layout/inspector/tests/chrome/Makefile
+    layout/mathml/tests/Makefile
     layout/reftests/fonts/Makefile
     layout/reftests/fonts/mplus/Makefile
     layout/style/test/Makefile