var menuids=["menu"];

 function buildsubmenus_horizontal(){
 	var ml = menuids.length;
 	for (var i=0; i<ml; i++){
 		var ultags=document.getElementById(menuids[i]).getElementsByTagName("ul");
 		var l = ultags.length;
 		for (var t=0; t<l; t++){
 			if (ultags[t].parentNode.parentNode.id==menuids[i]){
 				ultags[t].style.top=ultags[t].parentNode.offsetHeight+"px" //dynamically position first level submenus to be height of main menu item
 				ultags[t].style.left = ((ultags[t].parentNode.offsetWidth-110)/2) + "px";
 			}
 			else{ //else if this is a sub level menu (ul)
 				ultags[t].style.left=ultags[t-1].getElementsByTagName("a")[0].offsetWidth+"px" //position menu to the right of menu item that activated it
 			}
 			ultags[t].parentNode.onmouseover=function(){
 				this.getElementsByTagName("ul")[0].style.visibility="visible"
 			}
 			ultags[t].parentNode.onmouseout=function(){
 				this.getElementsByTagName("ul")[0].style.visibility="hidden"
 			}
 		}
 	}
 }

 if (window.addEventListener)
 window.addEventListener("load", buildsubmenus_horizontal, false)
 else if (window.attachEvent)
 window.attachEvent("onload", buildsubmenus_horizontal)