[Dovecot] LMTP: Rejecting unknown users

[Timo Sirainen]

On Wed, 2010-08-04 at 17:00 +0200, Peer Heinlein wrote:
> root at mail-archiv:/etc/dovecot# doveadm user notexistent at example.org
> userdb lookup: user notexistent at example.org doesn't exist

What if you run this twice, does the second one say it doesn't exist or
does it then return the user?

> But the user still exists if his Maildir is deleted:

Yeah, that isn't checked.

> ...and the user still exists after a complete restart of Dovecot?!

Sounds like LDAP server starts returning different replies. Restarting
it probably resets it? You should be able to reproduce the "doveadm
user" lookup the same way with "ldapsearch" by giving the same search
queries etc.

So to me this sounds like something weird going on with your LDAP
server..