Sendmail: How does one blacklist annoying spammers?

[Tim]

On Sun, 2010-06-27 at 14:08 -0400, Genes MailLists wrote:
>  So if you're gonna gray list - please whitelist all the standard ISP
> outbound mx hosts ...

That's gotta be a huge list.  And won't some of them be spam sources,
anyway?

-- 
[tim at localhost ~]$ uname -r
2.6.27.25-78.2.56.fc9.i686

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