I'm currently running a Snow Leopard Server, and trying to get anything useful working with the v1.1 version of Dovecot bundled with it is as pleasant as banging my head against a brick wall.
Dovecot's extremely sparse documentation has a lot of mentions of horribly-crippling bugs (specifically with public mailboxes and permissions) in 1.1 that were only fixed in 1.2. Which is not helpful for me since Apple has their own frustratingly-special blend of dovecot build (1.1.20apple0.5) for Snow Leopard Servers.
So, does the new Lion Server have enough Dovecot functionality to make it worth using?