function ToggleDIV(e, t, d1, d2) { 
    if (isMouseLeaveOrEnter(e, t)) {
      document.getElementById(d1).style.display = "none";
      document.getElementById(d2).style.display = "block";
    } 
  }
    
  // this function determines whether the event is the equivalent of the microsoft
  // mouseleave or mouseenter events.
  function isMouseLeaveOrEnter(e, handler)
  {		
	if (e.type != 'mouseout' && e.type != 'mouseover') return false;
	var reltg = e.relatedTarget ? e.relatedTarget :
	e.type == 'mouseout' ? e.toElement : e.fromElement;
	while (reltg && reltg != handler) reltg = reltg.parentNode;
	return (reltg != handler);
  }
  
  function init() {
  var panels = new Array('TLOverlayDiv', 'TROverlayDiv', 'BLOverlayDiv','BROverlayDiv');
	 for(i = 0; i < panels.length; i++)
    {
      document.getElementById(panels[i]).style.display = 'none';
    }
  }