sfHover = function(){
	var sfEls = document.getElementById("nav").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"), "");
		}
	}
}
window.onload = sfHover;