We are planning to setup a zimbra mail server on one of our remote site and I'm just wondering if Zimbra would work together with Exchange 2003?
The Zimbra mail server will be located on the remote site, but all their email transactions would be relayed/routed on our exchange 2003 server here in HQ then finally be routed outside in public. On microsoft terminology, we would just setup a routing connector group from the site to the HQ and vice versa.
But I have no idea how to do this on linux..

Would we encounter some issues using this setup?