> You might want to point out to them that rewrite_header breaks any DKIM > signature on mail,
Hmmm, good point, not really thought about this even. Are email clients complaining about this? > in addition to cluttering the Subject if > misclassified mail is part of a conversation. So the alternative is adding a header and move it to the spam folder automatically on the basis of the header? Currently I just want to 'warn' users that the message is possible spam, they can decide to move such emails automatically to a spam folder by enabling a sieve rule. What would be an alternative method to keep such functionality without altering the subject?
