What I would like to do is create a Linux "mirror" of our current windows server. Login and file sharing is taken care of using Fedora directory service, Samba and Rsync. I would like to use Zimbra as an exchange replacement. (This setup is partly for backup, partly for future migration). Two questions:

1. Is it possible to authenticate Zimbra with Fedora directory service? (FDS contains windows sync to keep it up to date with Active directory)

2. What would be the best way to keep Zimbra and exchange in sync? I was looking into using imap and Mailsync. Has anyone any experience with something like this?