var old='';
function menu(name)
{
	submenu=document.getElementById("submenu_"+name);
	if(old!=submenu)
	{
		if(old!='')
		{
				old.style.display='none';
		}
		submenu.style.display='block';
		old=submenu;
	}
	else
	{
		submenu.style.display='none';
		old='';
	}
}