MacOS X 10.2.2 has just been released. As always there is a document describing what’s changed. It’s unexplicable to me why they have not fixed the bug with Mac Mail not recognizing the IMAP-Folder-Prefix, leading to IMAP-Folders not being displayed. Apple itself suggests quite a stupid workaround: Create another dummy-accout and the folders will be displayed.
After all just setting the IMAP-Folder-Prefix in the Account-Properties to “INBOX” does help in most of the cases without having the user to create a dummy account. Anyway: This is clearly a bug and should be fixed by Apple. I don’t know why the did not.