navHover=function()
{
 navRoot=document.getElementById('topnav');
 if(navRoot!=null)
 {
  for(var i=0;i<navRoot.childNodes.length;i++)
  {
   aNode = navRoot.childNodes[i];
   if(aNode.nodeName=="LI")
   {
    aNode.onmouseover=function()
    {
     this.className+=' over';
    };
    aNode.onmouseout=function()
    {
     this.className=this.className.replace('over','');
    };
   };
  };
 }
 else
  alert('no nav found');
};
if(window.attachEvent && parseInt(navigator.userAgent.substring(navigator.userAgent.indexOf('MSIE')+5))<7)
 window.attachEvent("onload",navHover);