I dont see the curent page being highlighted in any browser, chrome, safari, or firefox. looking at the source code of your page, it doesn't look like you you have set the option to highlight the active menu item.
I see this code:
<script type="text/javascript">if(window.attachEvent) { window.attachEvent("onload", function() { cssmw.intializeMenu('cssmw',{select_current: 0, orientation: 2}); }); } else if(window.addEventListener) { window.addEventListener("load", function() { cssmw.intializeMenu('cssmw',{select_current: 0, orientation: 2}); }, true); }</script>
the "select_current: 0," means that select currant menu item is turned off.
it should be set to 3 to highlight the main menu item::
<script type="text/javascript">if(window.attachEvent) { window.attachEvent("onload", function() { cssmw.intializeMenu('cssmw',{select_current: 3, orientation: 2}); }); } else if(window.addEventListener) { window.addEventListener("load", function() { cssmw.intializeMenu('cssmw',{select_current: 3, orientation: 2}); }, true); }</script>