Ave!

I have recently created a postfix/courier mail server; postfix is responsible for SMTP and virus scanning, courier - for managing mailboxes (maildrop, pop3, imap). The server works, with one minor glitch.

The server is responsible for the @ios.krakow.pl domain. If it receives a letter for a non-existent user (fghw...@ios.krakow.pl) it accepts it, scans it for viruses and tries to deliver it. Of course, maildrop returns "user not found" error code. Postfix, on the other hand, interprets this code as "temporary failure" and on the next run tries to deliver the message again. Eventually, the message times out and is returned to the sender.

My question is: is there a way to make maildrop return a "fatal error" instead of "temporary failure" to postfix without recompiling the program? Or the other way around: to make postfix treat maildrop "user not found" errors as fatal?

I know I can make postfix only accept known addresses but maintaining that database is additional work.

The server is running a bit modified Debian Woody.

Thanks in advance,