There is a need to be able to publish a NO, I DONT WANT YOUR CRAP, DONT
EVEN SEND ME THE FIRST EMAIL, and based on a number of other refusals by
the IESG and IETF Management (based on demands from parties who's sales
of filters may be impacted) has refused to take a formal project to
'provide additions to DNS to allow for the publication of IP Licensing
and US/Contact Information for those domains.
RFC 3665. Nobody ever used it.
I'm fairly sure you mean RFC 3865, "A No Soliciting Simple Mail
Transfer Protocol (SMTP) Service Extension" but you're right, nobody
ever used it.
We never thought anyone would, but there was political pressure at the
time from people who didn't (and I see some still don't) understand
the "voluntary" part of the way standards work.
R's,
John