Hundreds of NDRs

[Chipshead]

Exchange 2003 SP2. We occaisionaly have users who get a few NDRs over a couple 
of days from reipients they did not send to because of spammers spoofing their 
email address. At 12:15 I have a user who began getting hundreds of NDRs 
obviously as a result of a spammer sedning out a bulk email package. These are 
coming in so fast the user is having a hard time keeping up with the deleting. 
Anyway to prevent this crap?
Thanks.
~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~
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