public function getAttributes($updated = false)
    {
        if (! $updated) return $this->attributes;

        $attributes = array();
        foreach ($this->attributes as $key => $value) {
            if (! array_key_exists($key, $this->o_attributes) || $value != $this->o_attributes[$key]) {
                $attributes[$key] = $value;
            }
        }
        return $attributes;
    }