How can I disable Amavis bounce messages?

[Jeff Morris]

I just noticed that my Amavis installation is sending out bounce 
messages such as the one below.

How do I shut these off? This is creating huge amounts of backscatter 
and getting me listed in RBLs. :-(

I don't see anything obvious in amavisd.conf.

I've tried to RTFM, but alas, although I can find lengthy diatribes 
discussing the philosophical merits of whether or not to turn them off 
(https://www.ijs.si/software/amavisd/README.policy-on-notifications.txt), 
and detailed instructions on how to customize them 
(https://www.ijs.si/software/amavisd/README.customize.txt), I can't find 
anything simply explaining how to turn them on or off. Frustrating. :-( 
Am I just looking in the wrong place? (Probably.)

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From: "Content-filter at colo1.nullmodem.org" <postmaster at nullmodem.org>
To: <sender at somedomain>
Subject: BANNED contents from you (.asc,credit_card_details_2E0B4_PDF.vbs)

BANNED CONTENTS ALERT

Our content checker found
     banned name: .asc,credit_card_details_2E0B4_PDF.vbs

in email presumably from you <sender at somedomain>
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