protected function set_boundaries()
	{
		$uniq_id = md5(uniqid(microtime(true)));

		// Message part boundary, (separates message and attachments).
		$this->boundaries[0] = 'B1_'.$uniq_id;

		// Message body boundary (separates message, alt message)
		$this->boundaries[1] = 'B2_'.$uniq_id;

		$this->boundaries[2] = 'B3_'.$uniq_id;
	}