I'm have been going over and over the forums and wiki's but still can't fully get my Zimbra installation working completely. I have my Zimbra box set up as a secondary system in a split domain. I've executed the commands needed for a split domain according to the split domain wiki. I have an internal mx record for the the Zimbra server.

Currently we have an old postfix/imap server and I'm not sure how I cant get users to communicate with the new system. I had Zimbra's mx record pointing to the same domain of the existing system but Zimbra support said that won't work.

So if my current working email server has an mx record for example.com, would I have to take that out and make example.com point to Zimbra and then Zimbra will route to the old email server?