mailmng is a python script which processes mail folders. It can copy messages from one folder to another, remove old messages from a folder or a combination of both. It therefore replaces amx and catmailuniq and has the advantage that it works with Maildir and IMAP as well as mbox. It also works without needing to create extra clutter in working directories like catmailuniq.
Download mailmng (version 0.6)
for usage details.