On Sat, Apr 12, 2008 at 5:06 PM, Marcin Cieslak saper@system.pl wrote:
If anything, I would recommend using DKIM (DomainKeys Identified Mail) rather than SPF. Please see http://www.dkim.org/
Their list of supporters is unimpressive:
http://www.dkim.org/deploy/supporters.html
I notice the absence of, for instance, Microsoft and Google. I know Gmail uses SPF; I don't know if it uses DKIM. The concept of DKIM seems like a better idea (public keys instead of enumerating IP addresses), but that's not helpful if it's not supported by major mail relays.