new rules - host or domain name not found

[tasmer]

I redirected the bounce on gmail and phpmailer not recognizes the bounce type.
I add this rule :

elseif( preg_match( "/Host or domain name not found/is", $diag_code ) ) {
                    $result['rule_cat'] = 'unknown';
                    $result['rule_no'] = '0237';
                    $result['bounce_type'] = '5.4.4';
                }

Here the mail content :

<[email protected]>: Host or domain name not found. Name service error for
    name=surlalune.lu type=AAAA: Host not found

Final-Recipient: rfc822; [email protected]
Action: failed
Status: 5.4.4
Diagnostic-Code: X-Postfix; Host or domain name not found. Name service error
    for name=surlalune.lu type=AAAA: Host not found