function showSubMenu () {
	this.getElementsByTagName('ul')[0].style.visibility = 'visible';
}
function hideSubMenu () {
	this.getElementsByTagName('ul')[0].style.visibility = 'hidden';
}

function popup_menu (js_id, type, popup_level, mixed_popup_level) {
	submenu = document.getElementById(js_id).getElementsByTagName("ul");
	for ( var i = 0; i < submenu.length; i++ ) {
		var reg = /.*active.*/;
		var reg_level = /lvl(\d+)/;
		var result = reg_level.exec(submenu[i].className);
		level = result == null ? false : result[1] ;
		if ( type == 'popup' || !reg.test(submenu[i].className) || level+1 >= mixed_popup_level ) {
			submenu[i].parentNode.onmouseover = showSubMenu;
			submenu[i].parentNode.onmouseout = hideSubMenu;
		}
	}
}