sfHover = function() 
{     
var sfEls = document.getElementById("dropdownnav").getElementsByTagName("LI");     
for (var i=0; i<sfEls.length; i++) 
{         
    sfEls[i].onmouseover=function() 
    {             
        this.className+=" sfhover";         
    }         
    sfEls[i].onmouseout=function() 
    {             
        this.className=this.className.replace(new RegExp(" sfhover\\b"), "");         
    }     
} 
} 
if (window.attachEvent) window.attachEvent("onload", sfHover);