I thing its Hash but not 100% sure, in /etc/courier/userdb i can see somthing like this: foo@bar.de uid=1001|gid=8|home=/var/mail/virtual/foo/bar|shell=/bin/false|systempw=$1$/LflPFc9$hCFdIVl1qmLMNIsf1sI2G.|mail=/var/mail/virtual/foo/bar
Do you need to know the old password or is it sufficient to reset it? I would reset it, now that you have posted the hash here for all to see. It looks like it is probably an MD5 hash, but if it is a weak password, it would not take that long to search the hash space for a match.