Sorry, just had to comment on your statement about reverse lookup. Since
arin.net is the authority for IP numbers, they allocate them to the ISP who
purchases them and the responsibility for reverse lookup falls to that ISP.
Since most smaller ISPs have about two or three jumps to the owner of the
subnet, they usually don't ever get the responsibilty for the reverse lookup
so the reverse lookup method of filtering mail is absurd if not insane.
> Can you recommend a good spam filtering software which accepts
>incoming email and then filters it based on certain criteria (at the
>level) before the mail is delivered to the user's mailbox.
Netscape's Messaging server has a plug-in for custom filtering that works
rather well as long as you understand how it works.
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