[Mimedefang] how to undo Verisigns mess

[Joseph Brennan]

> Since recently, all .net and .com domains started to resolve, pointing to
> a  verisign owned server that shows a customized webpage.
> roaringpiguin.com.      900     IN      A       64.94.110.11


Arg!  Aside from forgeries, if legit mail is sent with a typo'd
domain, the only chance we have to tell the sender is to reject
during the smtp transaction.

And then of course there ARE the deliberate forgeries.

Checking for MX would probably affect too much legit mail (for
some value of 'too much').

I guess we want to know when the hostname in $Sender resolves
to 64.94.110.11 specifically.  Or to 127.0.0.1 and the like.
What's an efficient way to do it?

Joseph Brennan         Columbia University in the City of New York
Academic Technologies Group                   brennan at columbia.edu