[Dovecot] Redelivery of mdbox messages to pass through sieve

Hey,

I've been slack and haven't updated my sieve script for yonks, and finally got round to it. What I was wondering is whether there was a way to basically take all the messages from a folder and pass it through sieve again. I've found earlier messages in this list, but they were for Maildir format, not mdbox which I use now.

Does anyone know of a way to do this?

Cheers,

Hugh