over = function() {
	var sfEls = document.getElementById("nav_menu").getElementsByTagName("LI");
	
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" over";
			var links = this.getElementsByTagName("A");
			
			for (var j=0 ; j<=links.lenght; j++) {
				links[j].style.height = "1%";
				links[j].onmouseover = function() {
					this.style.height = "1%";
				}
			}
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" over\\b"), "");
		}
	}
}

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