Hm i dont know... this is a long version of the window status, in firefox it works, only when you right click on the link it shows the real link. In IE it works perfectly, right click doesnt show the real link.
<a href="http://www.mydomain.com/blablarefcodesomethingsomething" onmouseover="window.status='http://www.mydomain.com/';return true;" onfocus="window.status='http://www.mydomain.com/';return true;" onmouseout="self.status='';return true;">
But i think you want a code for firefox that doesnt shows the real link with right click right? (like IE does with this code)