I attempted to do a migration from a working Ubuntu 7.04 installation to Centos5 VM with a different hostname and IP address. I use it from grabbing mail from a bunch of pop3 servers but don't send out of the zimbra box. I followed the instructions here: http://www.zimbra.com/blog/archives/...er_server.html
To make a long story short, it didn't work, the web interfaces all still pointed to the old server name. I tried to recreate certs because imap and pop3 wouldn't even start but that hosed it even worse. So I attempted to move things back.
I started the old instance on the old server BUT I did change the IP address to the new IP so I wouldn't have to mess with all the ip forwarding and firewall rules. Now all mails gathered by fetchmail are sitting in the Deferred queue. No amount of requeuing or flushing will push them through.
I'm not a zimbra expert because it's honestly been troublefree so I'm not sure what logs to look in for mail queue issues. Any help would be greatly appreciated.