menuDropdown = function()
{
   if (document.all&&document.getElementById)
   {
      navRoot = document.getElementById("menu-main").childNodes[0];
      for (i=0; i<navRoot.childNodes.length; i++)
      {
         node = navRoot.childNodes[i];
         if (node.nodeName == "LI")
         {
            node.onmouseover = function() { this.className+=" over"; }
            node.onmouseout  = function() { this.className=this.className.replace(" over", ""); }
         }
      }
   }
}
window.onload=menuDropdown;