var lastMenuEl = null;
var lastSubMenuEl = null;

function menuOver(id)
{	
	lastMenuOff();

	srcEl = document.getElementById(id);
	sub_menu = document.getElementById('sub_'+id);

	srcEl.className='on';
	lastMenuEl = srcEl;

	if (sub_menu!=null)	
	{
		lastSubMenuEl = sub_menu;
		sub_menu.style.display = 'block';
	}
}

function subMenuOver(id)
{	
	subEl = document.getElementById(id);

	menuOver(subEl.id.substring(4,10));

	if (subEl.className=='off')
		subEl.className='on';
	else
		subEl.className='off';
}

function lastMenuOff()
{
	if (lastMenuEl!=null)		lastMenuEl.className='off';
	if (lastSubMenuEl!=null)	lastSubMenuEl.style.display = 'none';
}