var openNav = function(navid) {
	if(!$('nav_' + navid).hasClassName('nav_selected')) {
		$$('.nav_selected').each(function(elem) { elem.removeClassName('nav_selected'); });
		$$('.nav_sub').each(function(elem) { if(elem.visible()) { new Effect.BlindUp(elem, { duration: 0.1 }); }});
		$('nav_' + navid).addClassName('nav_selected');
		$('nav_sub_' + navid).show();
		//new Effect.BlindDown(('nav_sub_' + navid), { duration: 0.1 });
	}
}