Marc Perkel wrote:
> Daryl C. W. O'Shea wrote:
>> Marc Perkel wrote:

>>> SPF is rather useless. Spammers can publish SPF records.

>> Guess what Marc, spammers can publish ANY DNS records! That includes
>> TXT records, type 99 (SPF) records, and your precious A and PTR records.

> What spammers can't do is publish a forward confirmed RNDS that ends in
>, which would be a listed domain.

WTF does whitelisting a domain have to do with whether or not a spammer
can publish DNS records.

From a DNS "forgeability" standpoint "your" method of checking FCrDNS
and checking for SPF_PASS are on equal ground.