Created attachment 2250 [details] A test mail and the saved mails from the Draft folder after replying to the original and the forwarded mail When replying to an email that has been forwarded as attachment, the recipient address will be taken from the 'To:' header of the forwarded mail even if a 'Reply-To:' header is present. The expected behaviour is to send the reply to the mail address in the 'Reply-To:' header.
I cannot reproduce this with the lastest release(s). Your reported version is 2½ years old, so it could be that it has been fixed since.