search for: some_strange_name

I would like deliver not to automatically create subfolders for mails addressed to user+some_strange_name at domain.com, but nevertheless automatically create INBOX for new users. I'm not sure whether a new option like -M or -m -m would be appropriate, i.e., whether anyone needs the current -m behaviour. It looks to me like one would need to change mailbox_open_or_create_synced()...