function del($key)
    {
        if ($key !== $hash = $this->_normalizeKey($key))
            $key = $hash;

        $properties = &$this->_referDataArrayReference();

        if (array_key_exists($key, $properties)) {
            unset($properties[$key]);
            unset($this->__mapedPropObjects[$hash]);
        }

        return $this;
    }