The original message was received at Tue, 26 Mar 2013 00:13:20 +0100 from sau-55c56-or.sau.net.au [27.50.86.170] (may be forged) ----- The following addresses had permanent fatal errors ----- (reason: 550 5.1.1 ... User unknown) ----- Transcript of session follows ----- ... while talking to maildelivery.rz.uni-osnabrueck.de.: >>> DATA <<< 550 5.1.1 ... User unknown 550 5.1.1 ... User unknown <<< 503 5.0.0 Need RCPT (recipient)