I got the same one:
Hi! This is the ezmlm program. I'm managing the
mlist@listserver.jriver.com mailing list.
Messages to you from the mlist mailing list seem to
have been bouncing. I've attached a copy of the first bounce
message I received.
If this message bounces too, I will send you a probe. If the probe bounces,
I will remove your address from the mlist mailing list,
without further notice.
I've kept a list of which messages from the mlist mailing list have
bounced from your address.
Copies of these messages may be in the archive.
To retrieve a set of messages 123-145 (a maximum of 100 per request),
send an empty message to:
<mlist-get.123_145@listserver.jriver.com>
To receive a subject and author list for the last 100 or so messages,
send an empty message to:
<mlist-index@listserver.jriver.com>
Here are the message numbers:
22
--- Enclosed is a copy of the bounce message I received.
Return-Path: <>
Received: (qmail 4441 invoked for bounce); 6 Apr 2012 06:48:37 -0000
Date: 6 Apr 2012 06:48:37 -0000
From: MAILER-DAEMON@webserver.jriver.com
To: mlist-return-22-@listserver.jriver.com
Subject: failure notice
The mail address it's referring to is an old address (not included in this mail). I moved from that ISP years ago, but the mail are still ticking in now and then. This is another address than my profile mail. I do not know where this one is stored or how to remove it. It's my original forum signup and JRiver purchase mail address.