function menu_second_shl(id, level) {
	var img_src = $('icon_'+id).src;
	var el_sub = $('sub_'+id);
	if (!el_sub) return;
	if (el_sub.getStyle('display') == 'block') el_sub.setStyle('display', 'none');
	else el_sub.setStyle('display', 'block');
	if (/plus/.test(img_src)) {
		img_src = img_src.replace(/plus/, 'minus');
	} else {
		img_src = img_src.replace(/minus/, 'plus');
	}
	$('icon_'+id).src = img_src;
}