I wasn't on the list for the first part of this discussion, but a quick perusal of the archives suggest that noone has yet suggested the use of Courier:http://www.courier-mta.org/I use it to do exactly what you describe. I would be glad to provide the specific details if you might be interested in a Courier approach.Well, to be honest, I hadn't got that far. At the moment I'm just talking about delivering mail to a local folder, probably preferably a Maildir one.Then, yes, I'd either use courier or cyrus.
I was suggesting the use of Courier both as an MTA and for IMAP/POP. In this case the configuration is very simple. There are two FAQ questions on their site that outline some of the virtual domain configuration principles:
http://www.courier-mta.org/?FAQ.html~virtual http://www.courier-mta.org/?FAQ.html~vdomainsI personally use the userdb setting explained in the first link. The "home" that you set there does not need to be a user account, simply a location where mail can be delivered (remember you need to create the Maildirs yourself). I use /var/www/example.com/user.
I would be glad to provide additional information or to answer any questions if you pursue this route. It is very simple to configure, and I like that fact that the MTA, POP, and IMAP all use the same configuration information.
Charles