I believe that this issue has been mentioned before but I wanted to post this just as a potential help to everyone now & in the future.
Kudos to the Zimbra engineers. Great stuff. Really great stuff. Specifically, kudos to them on their installer & their upgrade script. That script is getting better with each release, it checks more things, it has more sanity checks, it has more data checks, and I agree that is a very good thing to do, since changing versions of softwares is so damn tricky, and so much work, and so critical (especially with a 1000 users looking sideways at you while you do this) and I just wanted to mention that upfront. Keep it up. Add even more improvements.
Now, as to my main point:
I upgraded a Compaq Porliant dl380 server running centOS 4.6 last night from Network edition 5.0.0 GA to 5.0.5 GA. The upgrade took about 20 minutes or so, which was a long time, but I understand it has a lot of work to do to bring every piece of software from 5.0.0 to 5.0.1, then 5.0.1 to 5.0.2, then 5.0.2 to 5.0.3, then 5.0.3 to 5.0.4, then finally 5.0.5. I guess if we did more frequent upgrades (which we dont like doing) but if we did more frequent upgrades, the upgrades I did do would not take as long, since I am actually doing 5 upgrades in one, arent I?
The upgrade went straight through & everything came back up fine & mail started flowing immediately. But at one point, smack dab in the middle of the upgrade, I panicked when I saw this:
ERROR: account.NO_SUCH_SERVER (no such server: mail.example.org)
I believe it was around the section about LDAP but I can not be 100%.
Again, no real urgency here, everything seems fine, but I wanted the engineering to know that this kicked-out during the upgrade without any more information or instruction and they can post to this thread if they think it is important to do so or if they think that this is a real problem/issue that I need to resolve.