The original message was received at Wed, 5 Mar 2008 18:53:48 +0100 (CET) from localhost [127.0.0.1] ----- The following addresses had permanent fatal errors ----- <[email protected]> (reason: 550-Callout verification failed:) ----- Transcript of session follows ----- ... while talking to mail-gw.ise.fraunhofer.de.:

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DATA <<< 550-Callout verification failed: <<< 550 550 Unknown user: solar-energy 550 5.1.1 <[email protected]>... User unknown <<< 503 valid RCPT command must precede DATA