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