This is my guess :
When a mail arrives at the postfix queue, it is picked up by the pickup process. You have configured pickup to use dkimsign on port 10026 as a content filter (in masster.cf). port 10026 is the configured port for dkimproxy_in, which forwards to 10029. postfix listens on port 10029 but defines no content_filter there (you have a -o content_filtre=<nothng> there) What happens if you put amavis instead ? like this : 127.0.0.1:10029 inet n - n - 10 smtpd -o content_filter=smtp-amavis:[127.0.0.1]:10024 It might get you in a loop though (I've already seen this : http://imgur.com/aUAsuR1) so be sure to take necessary precautions. -- Yassine
