Using IMAP is how we've always had to setup Apple Mail. It's not possible to run IMAP over port 443 at the same time as using the web client and Outlook connectors.
You can read more about the integration with (current and potentially future) OS X Snow Leopard and Zimbra here
http://www.zimbra.com/forums/isync-c...tml#post141080
The setup for Apple Mail will just be the same as it would be for any other IMAP client that you have configured to your server.