Postfix + MySQL com erro "BAD UID"

Olá, implementei o "howto" do Postfix+MySQL+SASL+Courier-IMAP+Quota, porem ele me dá esse erro...

Feb 11 13:09:07 casper postfix/postfix-script: starting the Postfix mail system
Feb 11 13:09:07 casper postfix/master[1443]: daemon started -- version 1.0
Feb 11 15:09:15 casper postfix/pickup[1444]: 770C92C363: uid=0 from=<root>
Feb 11 15:09:15 casper postfix/cleanup[1450]: 770C92C363: message-id=<[email protected]>
Feb 11 15:09:15 casper postfix/nqmgr[1445]: 770C92C363: from=<[email protected]>, size=271, nrcpt=1 (queue active)
Feb 11 13:09:15 casper postfix/virtual[1456]: 770C92C363: to=<[email protected]>, relay=virtual, delay=0, status=deferred (recipient [email protected]: bad uid 89 in virtual_uid_maps)

já verifiquei o UID do user postfix no sistema, já verifiquei as permissoes dos usuarios nas pastas...

sinceramente não sei mais oq fazer!

obs. o dominio NeRV.ORG é interno, roda isolado numa VPN, com IP Range classe C 192.168.1.0/24, onde:
MAGI = 192.168.1.1 = GW
Bhaltazar = 192.168.1.2 = DNS
Melchior = 192.168.1.3 = WWW/SMB
Casper = 192.168.1.4 = SMTP/POP/IMAP

[brunomarcelo]

adiciona isto no main.cf

virtual_minimum_uid = UID