[Mimedefang] Bogus HELO filtering

[Joseph Brennan]

For what it's worth, in yesterday's mail, 22% of what we rejected
said 'HELO columbia.edu' and 11% more said 'HELO 128.59.59.105' --
those are *our* hostname and IP -- no further analysis needed:
59,000 messages tossed.

So I'd say checking HELO is worthwhile.  At least, reject mail that
claims to be from your own hostname and IP.

Joseph Brennan
Academic Technologies Group, Academic Information Systems (AcIS)
Columbia University in the City of New York