function togglemenu(type, object, number, menu) {
	if (menu == null) { menu = ''; }		
				 else { menu = 'l_'; }		
	 if (type == 'on') {
			object.src = '/lib/img/menu_' + menu + number + '_a.gif';
	 }
	 if (type == 'off') {
			object.src = '/lib/img/menu_' + menu + number + '.gif';
	 } 
}