function hasClass(ele,cls) {
	return ele.className.match(new RegExp('(\\s|^)'+cls+'(\\s|$)'));
}
function addClass(ele,cls) {
	if (!this.hasClass(ele,cls)) ele.className += " "+cls;
}
function removeClass(ele,cls) {
	if (hasClass(ele,cls)) {
		var reg = new RegExp('(\\s|^)'+cls+'(\\s|$)');
		ele.className=ele.className.replace(reg,' ');
	}
}

sfHover = function() {
	var sfEls = document.getElementById("nav").getElementsByTagName("LI");

	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			addClass(this,"sfhover");
		}
		sfEls[i].onmouseout=function() {
			removeClass(this,"sfhover");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", sfHover);