[Dovecot] Dovecot authentication issue with postgresql

[wernervdm at topbilling.com]

Good day,

I am having trouble getting dovecot to authenticate using postgresql.
For some reason, it fails on a PAM error, although I have specified pgsql
as authentication?

Here my setups:

dovecot.conf:
-- snip--  (not sure if you need teh rest)
auth = digest_md5
auth_mechanisms = plain digest-md5
auth_userdb = pgsql /etc/dovecot-pgsql.conf
auth_passdb = pgsql /etc/dovecot-pgsql.conf
auth_user = root

dovecot-pgsql.conf:
connect = host=localhost dbname=postfix user=postfix password=postfix
default_pass_scheme = MD5
password_query = SELECT password FROM mailbox WHERE username = '%u'
user_query = SELECT '/var/spool/vmail/'||maildir AS home, uid, gid FROM
mailbox WHERE username = '%u'


I get an authentication error trying to log in.
It queries the database for the password, but it does not seem to query
for user?

Logs:
dovecot:
dovecot-auth: Jul 05 05:14:41 Info: PAM:
pam_authenticate(chrisj at topbilling.com) failed: Authentication failure

messages:
Jul  5 05:14:39 tophat dovecot(pam_unix)[2928]: check pass; user unknown
Jul  5 05:14:39 tophat dovecot(pam_unix)[2928]: authentication failure;
logname= uid=0 euid=0 tty= ruser= rhost=

Any help will be greatly appreciated - the passwords are created using
postfixadmin - I presume it is in MD5 format.

Kind regards
Werner