window.onload = initClick;

var actField;
function initClick()
{
var i= 0;
var nav = document.getElementById("menu");	 
var allLinks = nav.getElementsByTagName("a");
	 for (i= 0; i<allLinks.length;i++){
		 allLinks[i].onmouseover = changeClass;
		 allLinks[i].onmouseout = setClass;
	 }
	 i = -1;
	 do{
	    i++;
		actField = i;
	 }
	 while(allLinks[i].className != "active")
}
			
function changeClass()
{
var nav = document.getElementById("menu");	 
var allLinks = nav.getElementsByTagName("a");
allLinks[actField].className = "";	
}
		
function setClass()
{
var nav = document.getElementById("menu");	 
var allLinks = nav.getElementsByTagName("a");
allLinks[actField].className = "active";	
}