Hi, I just came across a quite interesting idea. Greylisting naturally makes only sense if the remote end is no MTA, but a direct TCP connection. All MTAs will come back and thus greylisting will only introduce latency which most admins will see as neccessary tradeoff for reduced spam. Yet, why not use the knowledge of DNSBL to tell you which are the dialup-ranges of ISPs? Has anyone yet produced a config of say exim4 and greylistd using DNSBL for dialup hosts to trigger greylisting? That way all "regular" MTAs of providers and such remain whitelisted, and all dialup IPs may come back if they're a legitimate MTA for some sending user. If someone has any idea how to have exim4-daemon-heavy use the DNSBL for this, i'm all ears. Thanks! -- Best regards, Kilian
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