function ShowMenu(sub_menu,id)
{
    var el=document.getElementById(sub_menu);
	var child=el.firstChild;
	while(child)
	{
		if(child.tagName=="DIV")
		{
			child.style['display']='none';
		}
		child=child.nextSibling;
	}
	document.getElementById(id).style['display']='';
}