[Dovecot] Separate access to different "folders" of the same mailbox?

[Oli Schacher]

On Thu, 10 Feb 2011 09:15:18 +0200
Alexander Chekalin <achekalin at lazurit.com> wrote:

> in my company we have a mailbox that holds a copy of every message
> that our SMTP processed. While it eats a lot of space, it saved us
> several times when, you may imaging, user "suddenly" deleted the most
> important message in his life and call our IT guys for help. The
> mailbox contains "folders" for each day (like 2011-02-10), which
> keeps mailings for that day only.
[...]

What you are describing is basically a standard mail
archiving service. Instead of building this yourself you
could look at existing software tools that include the features you
describe and offer additional functionality like attachment indexing,
signed archives etc. For example Mailarchiva (mailarchiva.com) -
There is an open source version as well
( http://sourceforge.net/projects/openmailarchiva/ ) 
Google lists various other alternatives.

HTH

Regards,
 Oli