3 way sync?

[Simon Guest <simon@xxxxxxxxxxxxxxx>]

Hi,

I'm losing email trying to do a 3-way mail sync.  However, I'm not
sure that what I'm trying to do is supported by offlineimap, so here
goes ...

I have a 3 machines:

1. Server, running MS Exchange

2. Desktop, storing mail in Maildir format, and serving this over IMAP
   using courier-imap.

3. Laptop, storing mail in Maildir format.

I have a folder on the server I want to sync to all machines.  So I
run offlineimap on the desktop, sync'ing mail from the server into
~/Maildir/.server.INBOX (say).

I run offlineimap on the laptop, sync'ing mail from the desktop into
~/Maildir.  And I also (on the laptop), use offlineimap to sync mail from the
server into ~/Maildir/.server.INBOX.  (Note the subset relation in the
folder hierarchy.)

Suppose some mail arrives on the server.  I offlineimap it onto the
laptop.  Now it's on both server and laptop, but not on the desktop.
If I now offlineimap laptop with desktop, rather than copying the mail
to the desktop, it gets deleted from the laptop.

Does this sound familiar?  Any helpful suggestions, or is there more
useful information I could provide?

cheers,
Simon