One of those "rusty old Saturn V hulks" is actually inside an air-conditioned building. Not that it works any better than the others, but at least is looks prettier.
I hate to throw a commercial solution out here....
but, our company uses Lotus Notes and we have been satisfied with it. Not sure about its IMAP capabilities, but throw enough resources (servers) at it and take some time to learn how to manage it and things work pretty smoothly.
Slashdot Mirror
One of those "rusty old Saturn V hulks" is actually inside an air-conditioned building. Not that it works any better than the others, but at least is looks prettier.
I hate to throw a commercial solution out here....
but, our company uses Lotus Notes and we have been satisfied with it. Not sure about its IMAP capabilities, but throw enough resources (servers) at it and take some time to learn how to manage it and things work pretty smoothly.