[HowTo] Replace courier with dovecot

[Kotty]

i've added this to my server but now it doesn't accept any mails
this failure i've found at /var/log/mail.log

Quote:ispcp dovecot: auth(default): prefetch(test@xxx.de): passdb didn't return userdb entries

and then the mail is bounced back with

Quote:I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to postmaster. If you do so, please include this problem report. You can delete your own text from the attached returned message. The mail system <test@xxx.de>: user unknown

I think that problem is caused by the script but i don't find the failure.

Any ideas?