[Dovecot] Sieve as mail client?

[Tom Horsley]

A slightly off topic question, but maybe someone here has seen
something like this:

I want a program that operates entirely on the client side of
an IMAP server, and implements the sieve filtering language
by doing the necessary client side operations to move mail
on the IMAP server, expunge mail, etc.

It would also act as a proxy between my real mail client and
the IMAP server so I'd never see any mail that hasn't been
filtered first.

The benefits are obvious: I could finally get sieve filtering
on my stupid corporate exchange mail server :-).