This is ridiculous. Yet another bloody challenge-response patent. :(
http://about.mailblocks.com/press_0324_2003.html
... The Mailblocks service, available today, uses its patented technology
to eliminate spam ...
It's a simple challenge-response system. Nothing exciting or innovative
involved, as far as I can see. I can't find any patents in the uspto
database though. FYI,
--j.
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