public function addEURIDExtension()
{
$ext = $this->createElement('extension');
$authext = $this->createElement('authInfo:info');
$authext->setAttribute('xmlns:authInfo', 'http://www.eurid.eu/xml/epp/authInfo-1.0');
$authext->appendChild($this->createElement('authInfo:request'));
$ext->appendChild($authext);
$this->getCommand()->appendChild($ext);
}