On Mon, 2006-01-23 at 14:00 -0500, Jesse Chan-Norris wrote:
Maybe before with UW-IMAP you just had some "automatically expunge messages" option set?
I don't think that UW-IMAP was expunging messages because I could open up the mbox with pine and see all of the messages flagged as "Deleted" but not yet expunged. And when I try a similar test with Fastmail.fm (delete the message in Mail, then check using the web interface) the mail is marked as deleted in the web interface and does not show up in Mail.app but the messages are re-numbered appropriately.
Granted, I have no idea how Mail.app does its numbering (especially since Thunderbird doesn't have message numbering), but is it possible that there's more information that the IMAP server should be sending back that Dovecot isn't?
After trying this out for a while, I think I know what causes it. The difference with Dovecot and UW-IMAP is that UW-IMAP allows only a single connection to the mailbox (each new connection killing the old one), while Dovecot allows multiple.
Mail.app then goes and creates multiple connections to the mailbox, and after deleting the messages, it uses those different connections to fetch the mails. Then it somehow gets internally confused and starts renumbering the mails.