[Mimedefang] spamtrap on secondary MX

[-ray]

I read an article in SysAdmin that talked about setting up a spamtrap on a
secondary or tertiary MX box.  The box would look like a good MTA, answers
helo and 'mail from', but on 'rcpt to' always returns "451 Try again
later".  The idea being spammers prefer secondary MX's, but will never try
again.  A legit host that happens to connect will of course try again
later (hopefully to primary MX).  The author claims this reduced spam
intake by 10%.

Anyone done anything similar?  Any thoughts?  Seems like a simple way to 
catch a lot of spam...

ray
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Ray DeJean  				       	 http://www.r-a-y.org
Systems Engineer                    Southeastern Louisiana University
IBM Certified Specialist  	      AIX Administration, AIX Support
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