[RCU] Mail filtering with Courier?

Hello,

I'm a rather new roundcube user... I have it setup on my server and was looking at moving my userbase into it. However, I have one hang up...

mail filtering - I have spam filtering covered... My users tend to get large amounts of mail and need the mail filtered out into folders based on sender or header criteria.

I've searched through the forums and I came across a ManageSieve Filters plugin which looks perfect... for Dovecot - I'm using Courier IMAP as a backend.

I was wondering if anyone else is using Courier IMAP and what methods they are using to filter mail?

I know I have procmail and maildrop as backends, but I'm hoping for something I can present to my user base instead of writing filter scripts for each of them. :)

Thanks, Daniel

List info: http://lists.roundcube.net/users/