user known! but found.

[Marwan Sultan]

Hello everyone,

   I have a strange problem,

   There is a users has been added in my FreeBSD 4.8-R since over 6 months
   now.
   suddenly from no where, last 2 days, any INCOMING emails ONLY
   to this users it fails and it says "user known"
   Actually the user is in the system, im running the builtin sendmail.
   and qpopper, openwebmail, nothing special.

   I deleted that users totally, I add him again, but the same problem!
   I added a diffrent username, it works fine.

   I changed the Uid for the poor user it still doesnot accept
   incoming mails and says "unknown users" or "faild"

   I ran the command cat /etc/passwd|awk -F: '{print $1}'
   the users is listed, I checked /etc/passwd , users is listed,
   I can access user shell.

  /var/log/maillog   says:
  sm-mta[670]: hBHFWZpD000670: <derya at DOMAIN.net>... User unknown

  Can someone explain, whats this!
  any help appreciate it thanks.
  
  Marwan.