[Mailman-Users] Postfix refuses to relay for Mailman

[Maarten de Vries]

Hi all,

if this next question has been asked and answered before I'm sorry, but
I've spent all afternoon in vain google'ing to find that answer.

Here's what's wrong. I run Mailman 2.0.8 with Postfix (20010228.8_1), on a
machine which I'll call 'A.domain.name' here. I've installed Mailman as
'B.domain.name' (yes, 'B.domain.name' has a valid A-record), so when for
instance a user is added to a list, an e-mail will be sent from
'list-admin at B.domain.name' to 'user at external.domain'. This gives the
following error:

Jan  7 17:55:23 A postfix/smtpd[22053]: reject: RCPT from
localhost[127.0.0.1]: 554 <user at external.domain>: Recipient address
rejected: Relay access denied; from=<list-admin at B.domain.name>
to=<user at external.domain>

Obviously, Postfix doesn't want to relay mail for host 'B', which is on
the same server. I've tried tons of different options in main.cf (of
course followed everytime by a 'postfix reload', but no cigar.

What am I missing here? How do I tell Postfix to relay for host 'B'?

I know that this might not be the right list to post this on, but since
I'm told that Mailman is developed mainly on Postfix, I was hoping to find
some answers here still :-)

Thanks in advance,
-- 
mdv at unsavoury.net
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