var a = new Image(); a.src = 'images/root.gif';
var b = new Image(); b.src = 'images/hover.gif';
var c = new Image(); c.src = 'images/active.gif';

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