Here's another address to add to "SERVE OFF" and/or add to your
 lists' "Filter=" keyword.  The system, PALOALTO.EPRI.COM, is currently
 sending the delivery errors to the server address, which means the
 problem will take care of itself after 10 iterations.  But if they
 were to change their software to send the delivery errors to the
 proper address, the result would be a mail loop.  So, I'd still
 advise anyone with subscribers from that site to block mail from
 the "mailop" account as a precautionary measure.
 
 -jj
 
 Aside to <[log in to unmask]>:  LISTSERV performs a number
 of tests on incoming mail to try to identify/trap mail delivery errors.
 If you're interested in a list of the conditions that trigger the
 delivery error detection, please let me know.  So long as your mail
 software lets you configure the mail headers or the message text
 used, the changes needed should be fairly simple.
 
----------------------------Original message----------------------------
Error occurred while processing file 5161 from [log in to unmask]: "Mail
has been received from a user which has been served out".
 
------------------- Message causing the problem (51 lines) --------------------
Return-Path: <@JHUVM.HCF.JHU.EDU,@CUNYVM.CUNY.EDU:[log in to unmask]>
Received: from JHUVM (NJE origin JHUSMTP2@JHUVM) by JHUVM.HCF.JHU.EDU (LMail
          V1.1d/1.7f) with BSMTP id 5159; Fri, 25 Mar 1994 01:19:52 -0500
Received: from CUNYVM.CUNY.EDU by JHUVM.HCF.JHU.EDU (IBM VM SMTP V2R2) with TCP;
   Fri, 25 Mar 94 01:19:51 EST
Received: from prod1.epri.com by CUNYVM.CUNY.EDU (IBM VM SMTP V2R2) with TCP;
   Fri, 25 Mar 94 01:20:38 EST
Received: from eprinet.epri.com by prod1.epri.com (AIX 3.2/UCB 5.64/4.03)
          id AA11623; Thu, 24 Mar 1994 22:27:24 -0800
Received: from PALOALTO.EPRI.COM by SSW.EPRI.COM
        (Soft*Switch Central V4L380P5) id 430619220094083FPALOALTO;
        24 Mar 1994 22:19:22 PST
Message-Id: <[log in to unmask]>
Date: 24 Mar 1994 22:19:22 PST
From: "Postmaster" <[log in to unmask]>
Subject: DISTRIBUTION STATUS
To: [log in to unmask]
Comment: MEMO 03.24.94 22.19
 
                  SOFT-SWITCH
SMTP.LISTSE44     DISTRIBUTION STATUS INFORMATION        03/24/94 22:19
00
=======================================================================
 
DISTRIBUTION ID: SMTP.LISTSE44.1171
SUBJECT        : Output of your job .SKEPTIC.
DATE  SENT     : 03/24/94        TIME SENT: 21:06:00
=======================================================================
 
YOUR MAIL WAS NOT DELIVERED FOR THE FOLLOWING REASON:
 
SNADS STATUS  : 0501
EXPLANATION   : CANCELED
 
=======================================================================
 
RECIPIENT      : SMTP.JPACCIOR
LAST NAME      : JPACCIOR
FIRST NAME     :
MIDDLE INITIAL :
NATIVE NAME    : [log in to unmask]
COUNTRY        :
ADMD           :
PRMD           :
ORGANIZATION   :
ORG UNIT 1     :
ORG UNIT 2     :
ORG UNIT 3     :
ORG UNIT 4     :
DDA            : RFC-822!JPACCIOR(a)EPRI.EPRI.COM