I'm a longtime cyrus user, and have switched to Zimbra for a number of reasons. Our site has a growing Zimbra install, and I'm hoping it's going to supplant Exchange at some point, but in order for this to work, there are the niggling little things that need to get solved.
The current issue is duplicate e-mail messages. Cyrus is smart enough, for example, to only deliver one copy of a message to my inbox with the same msgid. This means that when someone sends mail to a mailing list I'm on and CCs me as well, I get only one copy in cyrus.
Not so with Zimbra. I've, at times, received up to four copies of the message (via IMAP or in the web client directly, as well as with my Windows Mobile device using Zimbra Mobile) due to a number of mailing lists being in the recipient list -- all of the duplicates having the same msgid.
I've tried putting the following in my .procmailrc on our mail relay:
### Duplicate filter
| formail -D 262144 /homes/stace/msgid.cache
| $DELIVERIT user.$CYUSER
(the second part of the recipe delivers anything tagged as a duplicate to my inbox on the mail relay server. A later rule delivers all messages that pass through the rest of the procmailrc to my Zimbra mailbox)
It doesn't fly. It catches *some* duplicates, but not all. In fact, not most.
But I shouldn't have to try to catch this in procmail. Is there some method to prevent duplicates in Zimbra that we're missing? Are others hitting this issue?