public function exportAsAttachedFile($name = "")
    {
        $this->_save();
        if (headers_sent($filename, $linenum)) {
            throw new OdfException("headers already sent ($filename at $linenum)");
        }
        
        if ($name == "") {
            $name = md5(uniqid()) . ".odt";
        }
        
        header('Content-type: application/vnd.oasis.opendocument.text');
        header('Content-Disposition: attachment; filename="'.$name.'"');
        readfile($this->tmpfile);
    }