Setting sendmail to auto block repeated denied sender?

[Dragoncrest]

	HI all.  Shot in the dark here, but I was just wondering if there was a 
way to get sendmail to automatically block or discard any messages 
(preferably discard) any messages from a particular email address that are 
repeatedly rejected due to unresolvable domain names.  About every day I'll 
get a spam message that has an invalid email addy on it that won't resolve, 
so when fetchmail tries to deliver it, it gets rejected and fetchmail 
doesn't delete it off the server.  I'd like to eliminate that of 
possible.  I would like sendmail to automatically just set that particular 
rejected email address to auto discard after 10 consecutive rejections for 
a period of 24 hours so that fetchmail doesn't allow a ton of mail to pile 
up on the remote server because the local sendmail instance is rejecting 
its delivery.

	If this is possible, let me know how to do it.  Thanks.