function removeAggregateObject($classname)
    {
        $ok = false;
        $classname = strtolower($classname);
        reset($this->_method_map);
        while (list($method, $obj) = each($this->_method_map)) {
            if (is_a($obj, $classname)) {
                unset($this->_method_map[$method]);
                $ok = true;
            }
        }
        return $ok;
    }