Bugs
----
* libc-client changed behaveour:
  instead of:
        msinfo  /home/tpo2/mail/mailsync
  we now need:
          msinfo  mailsync
          
You're wellcome to implement any of these
-----------------------------------------
* maintaining message Status is broken again. Need to fix that.

* unless run wit -D a once existent folder will allways be
  recreated because mailsync remembers it in it's .msinfo store.
  How to reproduce:
  * create folder F
  * store some file there
  * sync
  * remove F on both sites
  * sync
  * F will be recreated on one site :-/

* refuse to run if .mailsync contains password and permissions are wrong

* test and/or find better solution to the problem when encountering a mailbox
  that does not match our default mailbox delimiter

* mailsync can't handle mailboxes that contain messages _and_ submailboxes

* why do some errors go to stderr and some to stdout?

* ideally sanitize_message_id should not have a side effect, but just
  return 1 or 0 if the message had to be modified or it should have
  enough information to print a sufficient error message, i.e. the
  mailbox where the message is originating from

* I'm not sure whether extra mailboxes in read_lasttime_seen and delete_boxes
  in write_lasttime is consistent

* mailsync is using '!'  as a hierarchy separator. This is unfortunate. IMAP
  4rev1 says mailbox names should be encoded in "modified UTF-7" that is
  contain only characters 0x20-0x7e. That means we should use a non-"modified
  UTF-7" character as hierarchy separator for mailsync ideally a character
  that has special meaning on all platforms as f.ex. newline?

* no_expunge runtime/compile option don't mix?

* Displaying "=?iso-8859-1?Q?Susanne" in Subject or From: is nonsense

* warn should be on by default

* spaces should not be replaced by dots in msinfo

* escape '<' in mailbox names...

* extern msg_string in msgstring.h is ugly

Nice to have
------------
* if no emails are being expunged mailsync should shut up

* synchronize Status

* move CLI options into config file

* calculate (direction == ...) immediately in copy_message

* provide an integrated function for print_lead, print_...

* switch to md5 as default algorithm

* include patches for new features from http://bugs.debian.org/mailsync

* #mhinbox refers to the "inbox" box in the Mail folder in #mh format. That
  means that synchronizing INBOX with #mhinbox is impossible right now
  because strcmp( "INBOX", "#mhinbox") yield false.
  It'd be nice if we could sync those. If we'd do that then we could as
  well do a "whatever" to "whatother" mapping (1:1), which would make 
  INBOX <-> #mhinbox just a special case of the more general 1:1 maping.
  
* replace "vector"s by "slist"s