I have an existing domain running on MS Exchange 2007.
I want to start adding my new users onto a Zimbra server, and then migrates a large chunk of the users to the new Zimbra box.

I found htt://wiki.zimbra.com/wiki/Split_Domain
which describes well the how to do things...
( I think at the moment I would keep exchange as primary and Zimbras a secondary)

I have found Split domain with Exchange as Primary SAMPLE - Zimbra :: Wiki
which describes how to do it on a MS Exchange 2003.

but MS exchange 2007 is quite different, and I would do with a step by step guide for the equivalent on my platform!
Did I miss it in the wiki / forum ?