From: Wietse Venema on 30 Apr 2010 21:24
> Symptom: Any message with a binary attached seems
> to end up looping.
> Anyone here wants a sample from the logs?
No-one is interested.
You have an SMTP-based before-queue content filter that takes
minutes of time to process a file, causing the Postfix smtpd_proxy_filter
CLIENT to time out.
Per the SMTP definition, repeated timeouts will result in
REPEATED DELIVERY ATTEMPTS.
It is these MULTIPLE DELIVERY ATTEMPTS that result in multiple