I have followed the postfix+mysql tutorial at workaround.org ( http://workaround.org/articles/ispmail-sarge/ ). Im at Step 9 now, Test Your Setup. When I telnet to the localhost I get no errors when I enter what the site tells me to enter: # telnet localhost 25 Trying 127.0.0.1... Connected to localhost.localdomain. Escape character is '^]'. 220 localhost ESMTP Postfix (Debian/GNU) ehlo workaround.org 250-localhost 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250 8BITMIME mail from: 250 Ok rcpt to: 250 Ok data 354 End data with . This is a test email. . 250 Ok: queued as 4BE0979C055 quit 221 Bye Connection closed by foreign host. But when I look closer on the logfiles, something goes wrong: Aug 1 11:47:14 localhost postfix/smtpd[4400]: 4BE0979C055: client=localhost.localdomain[127.0.0.1] Aug 1 11:47:20 localhost postfix/cleanup[4406]: 4BE0979C055: message-id=<20060801114710.4BE0979C055@localhost> Aug 1 11:47:20 localhost postfix/qmgr[4398]: 4BE0979C055: from=, size=364, nrcpt=1 (queue active) Aug 1 11:47:20 localhost postfix/smtp[4409]: 4BE0979C055: to=, relay=none, delay=10, status=bounced ([virtual.test]: Name or service not known) Aug 1 11:47:20 localhost postfix/cleanup[4406]: 9877F79C056: message-id=<20060801114720.9877F79C056@localhost> Aug 1 11:47:20 localhost postfix/qmgr[4398]: 9877F79C056: from=<>, size=1986, nrcpt=1 (queue active) Aug 1 11:47:20 localhost postfix/qmgr[4398]: 4BE0979C055: removed Aug 1 11:47:21 localhost postfix/smtp[4409]: 9877F79C056: to=, relay=torf.workaround.org[212.12.58.129], delay=1, status=bounced (host torf.workaround.org[212.12.58.129] said: 504 : Helo command rejected: need fully-qualified hostname (in reply to RCPT TO command)) Aug 1 11:47:21 localhost postfix/qmgr[4398]: 9877F79C056: removed Aug 1 11:47:22 localhost postfix/smtpd[4400]: disconnect from localhost.localdomain[127.0.0.1] The "virtual.test" exists in my mysql database, so I have no idea why it says its not known. And there's one more error: ": Helo command rejected: need fully-qualified hostname (in reply to RCPT TO command)"