sfHover = function() {     
    var sfEls = document.getElementById("topnav").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);