function showShadow(evt, name){
   evt = (evt) ? evt : ((window.event) ? window.event : null);

   if(evt){
	    name += "-shadow";
      id = document.getElementById(name);
      id.style.visibility = "visible";  
   }
}

function hideShadow(evt, name){
   evt = (evt) ? evt : ((window.event) ? window.event : null);

   if(evt){
	    name += "-shadow";
      id = document.getElementById(name);
      id.style.visibility = "hidden";  
   }
}