class Application_Models_Category
{
	function allMenu()
	{
		$arr = array();
		$results = mysql_query("SELECT * FROM menu WHERE parent_id='0'");

		while ($rows = mysql_fetch_assoc($results))
			{
				$results_children = mysql_query("SELECT * FROM menu WHERE parent_id='$rows[id]'");
				
				while ($rows_children = mysql_fetch_assoc($results_children))
				{
					$rows[] = $rows_children;
				}
				
				$arr[] = $rows;
			}
		return $arr;
	}
}

class Application_Controllers_Category extends Lib_BaseController
{
	function index()
	{
		$model = new Application_Models_Category;
		$menu = $model->allMenu();
		$this->menu = $menu;
	}
}

		echo "<pre>";
		print_r($menu);
		echo "</pre>";