[Dovecot] Plain password auth issues

[nospam]

Have the following entries in dovecot.conf


auth_userdb = passwd-file /etc/dovecot-passdb
auth_passdb = passwd-file /etc/dovecot-passdb


auth_user = dovecot



passwd-file is owned by user and group dovecot


When I try to log in .. I get

dovecot: Feb 19 16:41:30 Error: Logins with UID 0 not permitted (user
echo)
imap-login: Feb 19 16:41:30 Info: Internal login failure: echo
[127.0.0.1]
dovecot-auth: Feb 19 16:41:30 Info: Login process 12 disconnected


Any ideas ?