- fix memory holes (e.g. imap->msgs)
- currently a buffer is enlarged up to the total size of the reply.
  This is bad, imagine what happens if people receive 10MB attachments.
- streaming of BODY fetch commands doesn't start until UID fetch is complete
- problem of flagging / unflagging  (unflagging doesn't get propagated)
- more statistics (messages, message size, elapsed time)
- cleanup of _ALL_ code
- finish NAMESPACE support
- automatic configfile generation (list mailboxes on one machine)
- STARTTLS 
- CRAM-MD5 authentication
- logfile support
- put sockets in nonblocking mode
- modify receive window according to needs? (see ietf-draft)
- sometimes 'error: message bigger than buffer, truncating' error
- error handling
- error handling
- error handling
