Milter-greylist

I think SPF would become very important for address and domain based 
whitelisting.  For instance if people here whitelisted 
milter-greylist@yahoogroups.com, what's to stop a spammer from sending 
mail with that from address?  SPF would.  I suppose the rule would be 
that in order to whitelist widely known domains like yahoo.com and 
google.com, you'd want to insist on SPF.


Bill Levering wrote:
> JMHO, but I enabled spf about 2 months ago, and it appears that a much 
> higher percentage of spammers are using SPF now.
>
> Yes, it alleviates the delay for valid email.. and spam.
>