Without diving too deep into this can of worms I'd like to point out
that rejecting mail due to SPF fails is a whole different ball-game-of-
wax than accepting mail due to an SPF pass -- the limitations related
to forwarding are well known, but orthogonal to whitelisting, which is
what this thread was originally about... A domain whitelist
(reputation) is useful whether the (authentication/authorization)
mechanism is SPF or DKIM or PTR.

On Jul 12, 2007, at 11:48 PM, "John D. Hardin"

> On Thu, 12 Jul 2007, Marc Perkel wrote:
>> I'm just tired of having to deal with the bad side effects of SPF
>> and expainging to people that the can't use my spam filtering
>> unless they turn SPF off.

> What's wrong with that?