[Evolution] Disable header changing in IMAP?

[Michael C. Neel]

It it possible to stop evo from changing headers over an IMAP connection?  Evo is currently changing headers (which really means downloading the message, and uploading a new one then deleting the original) and this is conflicting with my spam filter (SpamBayes) which also must change headers, and this is causing duplicates in my inbox of the same message.

If I can't stop evo, can it at least wait until I've opened the email to start changing the headers?

Thanks,
Mike