Dropping failed 'recieved notices' to the floor

I moderate several groups and send out automated "thanks for the submission,  
here's the rules" notes for them.

Of course now with all the spam and screwy email addresses, bounces are at  
an all-time high.

I really don't want to see those...

What header do I need to add to my formail construct to have them routed to  
/dev/null?

Thanks!

Scott


:0
* ^TOnext-announce
* !^FROM_DAEMON
* !^X-Loop: $LOOP_NAME
        {
        :0c:lockit
        | (formail -rt -A"X-Loop: $LOOP_NAME" -I "Subject:  
comp.sys.next.announce - ACK"; cat $NEXT_ANNOUNCE_AUTO_ACK) |$SENDMAIL -oi -t

        :0c
        |appnmail -r $LOGS_DIRECTORY/next-announce

        MESSAGE_LOG_FILE=$MAILDIR/next-announce-ACK
        INCLUDERC=$PROCMAIL_RC_FILES/procmail_log_message.rc

        }