[Keith in Iowa]

>>Define "kill sources of spam." <<

Is an ISP terminating service to someone good enough for you?

[alwayzright]

That doesn't kill a source of spam. You probably just got an open relay shut off. I assure you it takes much more to stop a spammer. If you're interested enough to go that far, do some research on the Internet. Tracking spammers is fascinating because it never ends. The spammers always find some new way to progagate their trash.