var navlist = document.getElementById("sub_nav").getElementsByTagName("li");
for(var i=0;i<navlist.length;i++)
{
	navlist[i].onmouseover = function(){
		this.style.background = "url(/images/sub_nav_onbg.gif) no-repeat";
	}
	navlist[i].onmouseout = function(){
		this.style.background = "url(/images/sub_nav_offbg.gif) no-repeat";
	}
}