Re: [Evolution] From POP3 to IMAP

[Pete Biggs <pete biggs org uk>]

> With e.g. imapsync I cync from every IMAP server to every IMAP server
> without losing the seen status. The IMAP protocol can handle the seen
> status without a problem.

Yes, and the seen/unseen status is held either in a database on the IMAP
server or in an application specific header in the mail message (if the
underlying format is mbox, and encoded in the filename for Maildir).
When the message is passed through the IMAP protocol, those format
specific flags are translated into a seen/unseen status within IMAP and
then ultimately stored in an application specific format on the target
server.  What's more, the X-* headers specific to the server application
are not externalised by the IMAP server - the user never sees them.

The same goes for Evolution: it stores the message status in the
X-Evolution header - the user never sees that header (why should they) -
however the header is used when talking to other servers.  And,
similarly, if you want to retain the status of the messages, then you
need to use the application itself (whether it be an IMAP server or
Evolution) to pass on the correct status of the message.


> So far I know Evolution stores it's "seen" status in such a header. So
> important to convert and very client specific.

Yes. So use the client to do the conversion/transfer. 

As far as I can see you have a number of options:

 1 - Do a straight mbox->cyrus conversion and lose all the flags

 2 - Get the users to move their own mail and retain all flags

 3 - Use mb2md.pl (which DOES understand X-Evolution headers) to create
a Maildir format mailstore, then use standard tools for getting those
Maildir mails into Cyrus.

 4 - Write a program that reads the mbox files, interprets the flags and
then talks to an IMAP server.  It's certainly something that's doable in
Perl, but not trivial.

The choice, as they say, is yours.

P.