function initNav()
{
	var nav = document.getElementById("nav");
	if(nav)
	{
		var lis = nav.getElementsByTagName("li");
		for (var i = 0; i < lis.length; i++)
		{
			lis[i].style.zIndex = 100 - i;
		}
	}
}

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