[Dovecot] disabling mail delivery for a user

[Frank Cusack]

On February 2, 2010 1:29:24 PM +0200 Timo Sirainen <tss at iki.fi> wrote:
> Logins would fail with "internal login failure". userdb lookup must
> succeed for imap/pop3 logins too. You could make the deny=yes happen only
> if %s != 'lda'.

A little more help?  I've been looking at the docs and can't figure out
how to do this.  I do have one constraint: my userdb/passdb is a
passwd-file.  If that's not compatible I'd still like to know how to
do it with LDAP (preferably) or SQLite.

-frank