$(function(){
  $("ul li:first-child").addClass("firstchild");
  $("ul li:last-child").addClass("lastchild");
});

hover = function() {
	var sfEls = document.getElementById("header").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" hover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" hover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", hover);// JavaScript Document