[MlMt] untangling accidental mailbox move

[Randy Bush]

i accidentally drag an imap mailbox to another one on the same server.
that server does not support sub-mailboxes.  so mailmate loops telling
me that deletion of the moved mailbox fails, and asks if i want to tey
later, take the account offline, or retry.

what i want is "oops, forget it."  expecially as, when i look at the
server, the messages are in the original directory.

barring that, can i hack some file in ~/Library/Application
Support/MailMate to undo this wedge?

randy