jsHover = function() {
	var lis = document.getElementById("dropdown_nav").getElementsByTagName("LI");

	for (var i=0; i<lis.length; i++) {
		lis[i].onmouseover=function() {
			this.className+=" jshover";
		}
		lis[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" jshover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", jsHover);