on Wed, Nov 10, 2004 at 08:25:43AM -0500, Rob McEwen wrote:
CBL catches a LOT of spam... but it also periodically will list the mailserver for respected IPS where that ISP had one user who send out a bunch of spam and then CBL listed the IP address of that server.
IME, it's not so much spam as virus-infected machines. One reason I continue to use CBL is that it keeps out 40% of the virus traffic I'd see otherwise - that the infected machines are often used as spam proxies is icing on the cake. And anything that encourages slacker mail admins to /stop emitting or proxying viruses/ is a good thing in my book. So I don't see what your problem is.
As for the issue of listing domains and IPs of known spammer domains; I've been doing this (listing IPs of found spammer domains and checking unknown domains against the IP blacklist) for several months and it's worked pretty well. In a nutshell, the spammers change IPs more slowly than they change domains. It's a useful check. But you have to be careful to expire those IPs from time to time, as they're subsequently reassigned (whether to other spammers or to legit businesses).