I have a setup that I'm working on migrating to Dovecot for thousands of
users across a few dozen domains.. All users are authed from LDAP.. In
LDAP, each user has a unique uidNumber, and varying gidNumber (for use
in other applications)
As far as mail storage, the entire Maildir structure is owned by
 UID/GID: vmail/vmail

So, the uidNumber/gidNumber from LDAP is not needed. global uid/gid is
set to 'vmail'

When using "passdb ldap" and "userdb ldap" both pointing to
dovecot-ldap.conf, and removing the "uidNumber=uid"..etc from the
"_attrs" lines, this works just fine.

I would like to use "userdb prefetch" to use one less ldap query, but
the uid/gid stuff is giving me some problems.

The appropriate line in - dovecot-ldap.conf:
pass_attrs = mail=user,userPassword=password,homeDirectory=userdb_home

I get the following erros in the log:

....
....
dovecot: auth(default): prefetch(user@domain.com,127.0.0.1): userdb_uid not returned
dovecot: auth(default): prefetch( user@domain.com,127.0.0.1): userdb_gid not returned
dovecot: auth(default): userdb(user@domain.com,127.0.0.1): user not found from userdb
dovecot: auth(default): master out: NOTFOUND 1
dovecot: pop3-login: Internal login failure: user=<user@domain.com>, method=PLAIN, rip=127.0.0.1 , lip=127.0.0.1, secured

Any help is appreciated!

-Mike

FreeBSD 6-1-RELEASE
OpenLDAP 2.3
Dovecot 1.0rc2