ezmlm-weed blocking bounce messages?

I'm running ezmlm-idx 5.1.0.  I was browsing through my qmail logs 
and saw indications that I was getting a lot of messages that were 
probably bounces for a specific list user, but those bounces never 
seemed to be getting into the list bounce directory to be processed 
by ezmlm-warn.

My list bouncer file is the standard one created by ezmlm-make, containing:
ezmlm-weed
ezmlm-return -D listdir

I guessed that maybe ezmlm-weed was throwing away the messages before 
ezmlm-return saw them, so I commented out the ezmlm-weed line.  My 
guess was correct, and after ezmlm-weed was commented out, the 
bounces ended up in the bounce directory.  They look like legitimate 
bounces for a non-existent user, so I don't know why ezmlm-weed 
thought they were weeds.  Here's an example, with the recipient 
address slightly munged for  privacy.

Received: (qmail 48797 invoked from network); 8 Feb 2007 23:09:25 -0500
Received: from plmler3-e0-2.mail.eds.com (HELO plmler3.mail.eds.com) 
(199.228.142.123)
   by crossbo.jmatt.net with AES256-SHA encrypted SMTP; 8 Feb 2007 
23:09:25 -0500
Received-SPF: none (crossbo.jmatt.net: domain at plmler3.mail.eds.com 
does not designate permitted sender hosts)
Received: from plmler3.mail.eds.com (localhost [127.0.0.1])
         by plmler3.mail.eds.com (8.13.8/8.12.10) with ESMTP id l193XjPN003178
         (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK)
         for <[email protected]>; 
Thu, 8 Feb 2007 21:33:45 -0600
Received: from localhost (localhost)
         by plmler3.mail.eds.com (8.13.8/8.12.10) id l193XjSq003169;
         Thu, 8 Feb 2007 21:33:45 -0600
Date: Thu, 8 Feb 2007 21:33:45 -0600
From: Mail Delivery Subsystem <[email protected]>
Message-Id: <[email protected]>
X-EDS-Source-Ip: 208.116.11.36
X-EDS-Source-Name: crossbo.jmatt.net
X-EDS-Reported-Name: localhost
To: <[email protected]>
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
         boundary="l193XjSq003169.1170992025/plmler3.mail.eds.com"
Subject: Returned mail: see transcript for details
Auto-Submitted: auto-generated (failure)

This is a MIME-encapsulated message

--l193XjSq003169.1170992025/plmler3.mail.eds.com

The original message was received at Thu, 8 Feb 2007 21:33:45 -0600
from crossbo.jmatt.net [208.116.11.36]

    ----- The following addresses had permanent fatal errors -----
<[email protected]>
     (reason: 553 5.3.0 <[email protected]>... Relay Validation 
Failed - User Not Found)

    ----- Transcript of session follows -----
... while talking to localhost:
>>>  DATA
<<< 553 5.3.0 <[email protected]>... Relay Validation Failed - User Not Found
550 5.1.1 <[email protected]>... User unknown
<<< 503 Need RCPT (recipient)

--l193XjSq003169.1170992025/plmler3.mail.eds.com
Content-Type: message/delivery-status

Reporting-MTA: dns; plmler3.mail.eds.com
Received-From-MTA: DNS; crossbo.jmatt.net
Arrival-Date: Thu, 8 Feb 2007 21:33:45 -0600

Final-Recipient: RFC822; [email protected]
Action: failed
Status: 5.3.0
Remote-MTA: DNS; localhost
Diagnostic-Code: SMTP; 553 5.3.0 <[email protected]>... Relay 
Validation Failed - User Not Found
Last-Attempt-Date: Thu, 8 Feb 2007 21:33:45 -0600

--l193XjSq003169.1170992025/plmler3.mail.eds.com
Content-Type: text/rfc822-headers

Return-Path: <[email protected]>
Received: from crossbo.jmatt.net (crossbo.jmatt.net [208.116.11.36])
         by plmler3.mail.eds.com (8.13.8/8.12.10) with ESMTP id l193XjSq003146
         for <[email protected]>; Thu, 8 Feb 2007 21:33:45 -0600
X-EDS-Source-Ip: 208.116.11.36
X-EDS-Source-Name: crossbo.jmatt.net
X-EDS-Reported-Name: crossbo.jmatt.net
Received: (qmail 44755 invoked by uid 1012); 8 Feb 2007 22:33:43 -0500
Comment: DomainKeys? See http://antispam.yahoo.com/domainkeys
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
   s=default; d=foxhunters.org;
   b=NI++qaACru6MvbRT5Ad5xun6V/OnAVYVy1UpBSpdY+XCxF3zzXKruPyMnsD6WiKd;
 
h=Mailing-List:Precedence:Sender:List-Help:Reply-To:To:Delivered-To:Received:Message-ID:Date:From:In-Reply-To:MIME-Version:Content-Type:Subject;
Mailing-List: contact [email protected]; run by ezmlm
Precedence: bulk
Sender: Foxhunters OnLine <[email protected]>
List-Help: http://foxhunters.org/
List-Unsubscribe: [email protected]
Reply-To: Foxhunters OnLine <[email protected]>
To: Foxhunters OnLine <[email protected]>
Delivered-To: mailing list [email protected]
Received: (qmail 21101 invoked from network); 8 Feb 2007 19:12:02 -0500
Message-ID: <[email protected]>
Date: Thu, 8 Feb 2007 16:11:45 -0800