showMenu = function() {
	var subMenuItems = document.getElementById("topMenu").getElementsByTagName("li");
	for (var i=0; i<subMenuItems.length; i++) {
		subMenuItems[i].onmouseover=function() {
			this.className+=" showMenu";
		}
		subMenuItems[i].onmouseout=function() {
		      this.className=this.className.replace(new RegExp(" showMenu\\b"), "");
		}
	}
}

if (window.attachEvent) window.attachEvent("onload", showMenu);