Brian Read wrote:
No they aren't that "rule" causes quite a few of my customers a headache, as the (linux) mailserver I often install sends the email direct, irrespective of whether there Ip is "dynamic" or "static". Some ISPs charge an arm and a leg for static IPs.Block all mails from dynamic IP. They are 99,99% spam.
I wind up blocking mail from people like that for an entirely different reason. Basic DNS checking against the HELO string to be sure it resolves to the IP address the connection's actually coming from. I couldn't imagine how much spam I don't even have to waste cycles filtering as a result. :-) Mind you, I wind up having to send "your mailserver isn't configured right" messages to some sites. But the reduction in the noise is well worth it.
This attack, for example, would all but be completely blocked without a single invocation of SpamAssassin. :-) Unless of course they luck out and infect a PC that has a proper mail config. :-\
Bill _______________________________________________ http://lurker.clamav.net/list/clamav-users.html
