--On 17 March 2011 09:27:31 -0700 Marc Perkel <marc@???> wrote:
> I was just wondering why the mailfrom option wasn't allowed in recipient
> callouts?
I'm not sure about this, but I think it's something like this:
mailfrom was introduced for sender verification callouts to work around the
situation where various clumsy and arguably rfc non-compliant
implementations of "bounce protection" cause the callouts to break, by
rejecting all bounce messages before DATA.
mailfrom wasn't deemed necessary for recipient verification callouts,
because they're supposed to be used internally to your site. That is, the
callout should be to a machine that you control in order to more reliably
determine whether the recipient is local to the site. We use them to
determine whether our list server will accept a message - it avoids the
need to put our list addresses into LDAP.
Since you're in control of the destination host, there doesn't seem to be a
need for mailfrom in recipient callout verifications.
--
Ian Eiloart
IT Services, University of Sussex
01273-873148 x3148
For new support requests, see
http://www.sussex.ac.uk/its/help/
