I do recall at one stage you had to create a symlink back to the base of the Maildir called INBOX for Mail.app to work:
ln -s Maildir/ Maildir/.INBOX Hope that helps Ned > > We've experienced some issues with courier-imapd and Mail.app, > specifically where certain IMAP sub-Maildir mailboxes wouldn't display > within Mail.app. The mailboxes work great within Thunderbird. > > It's been infrequent enough where we haven't really done a thorough > investigation. If anybody else has had similar issues, and knows of a > fix, please share! > > Thanks- > Eric