function initPage()
{
 var navRoot = document.getElementById("menu");
 var lis = navRoot.getElementsByTagName("li");
 for (var i=0; i<lis.length; i++)
 {
  lis[i].onmouseover = function()
  {
   this.className += " hover";
  }
  lis[i].onmouseout = function()
  {
   this.className = this.className.replace("hover", "");
  }
 }
}

if (window.attachEvent && !window.opera)
 window.attachEvent("onload", initPage);