startList = function() 
{
  if (document.all && document.getElementById)
    {
      node = document.getElementById("dropdown");
      if (node)
        {
          listItems = node.getElementsByTagName("LI");
          for (i = 0; i < listItems.length; ++i)
            {
              listItems[i].onmouseover = function()
                {
                  this.className += " over";
                }
              listItems[i].onmouseout = function()
                {
                  this.className = this.className.replace(" over", "");
                }
            }
        }
    }
}
window.onload = startList;