var ie=document.all //is it IE?

function showSubMenu(el){
	if (ie){ //do anything only if working on IE, other browsers will use css rollover
		collection=el.getElementsByTagName('ul');
		if (collection[0]){
		  collection[0].style.display='block';
		}
	}
 return true;
}

function hideSubMenu(el){
	if (ie){ //do anything only if working on IE, other browsers will use css rollover
		collection=el.getElementsByTagName('ul');
		if (collection[0]){
		  collection[0].style.display='none';
		}	
	}
	return true;
}