[Greylist-users] Possible Enhancements

[Steven Grimm]

James J Dempsey wrote:

>In this case, or in cases where the spammer simply uses "From:
>fill-in-the-blank at yahoo.com", this technique would completely  eliminate the
>effectiveness of greylisting.  Unless I'm not understanding your proposal properly.
>  
>
I took the proposal to mean, check the MX record for the domain in 
question, and let the mail through if the MX record contains the IP 
address of the sending host. Which would block joe-jobs unless the 
spammer listed his entire network of hijacked machines in his MX record 
(which would be handy for anti-spam people!)

The idea still isn't great IMO -- too easy for spammers who aren't using 
Joe-jobs to set up legitimate-looking MXs -- but if you interpret it 
this way it's not quite as bad.

-Steve