window.addEvent('domready', function() 
{

  // check that the li element has a ul child, of so display it on mouse over 
  $('navmenu').getChildren("li").each(function(e, i, a)
  {
    
    if (e.getChildren('ul').length == 1)
    {
      //Add Mouse over event 
      e.addEvent('mouseenter', function()
      {
        e.getFirst('a').setStyle('background-color', "#FFF");
        e.getFirst('ul').setStyle("display", "block");
        e.getFirst('ul').setStyle("z-index", "5");
      });
      
      //Add Mouse over event 
      e.addEvent('mouseleave', function()
      {
        e.getFirst('a').setStyle('background-color', "");
        e.getFirst('ul').setStyle("display", "none");
      });
    }
  });
});