I was just googling fro ispconfig + greylist and came across this thread.
We have a machine with ispconfig with a few domains and mailboxes in there, for some of our clients. However, for us, we use Exim + Dovecot with MySQL with setup idea taken from http://struction.de/projects/HOWTO_V...lamAV-Dovecot/
In this link, you find that exim does not need greylisting daemon. It simply stores the ip and e-mail address whenever a e-mail comes in, wlong with timestamp.
When the e-mail comes back in, it checks if there is a mysql row, the timestamp and if <treshhold time> minutes have past
Could this be implemented in ispconfig? A main postfix ACL that for every e-mail it checkes a greylist (AND NOT IN whitelist) table, and rejects temporarly if time treshhold is not yet reached???
(hope you can understand what I mean)