Every reply I'm receiving in a subscription is generating 2 e-mail notifications. I am not receiving duplicate messages from any other senders.

SMTP header from first notification:
---
Status: U
Return-Path: <admin@camaroz28.com>
Received: from mx-pigeons.atl.sa.earthlink.net ([127.0.0.1])
by mx-pigeons.atl.sa.earthlink.net (EarthLink SMTP Server) with SMTP id 1lj9jQ45f3Nl34g1; Sat, 3 Jan 2009 11:25:46 -0500 (EST)
Received: from ns.camaroz28.com ([64.65.56.121])
by mx-pigeons.atl.sa.earthlink.net (EarthLink SMTP Server) with ESMTP id 1lj9jQ53y3Nl34g0
for <omitted@earthlink.net>; Sat, 3 Jan 2009 11:25:46 -0500 (EST)
Received: (qmail 10634 invoked by uid 48); 3 Jan 2009 11:25:46 -0500
Date: 3 Jan 2009 11:25:46 -0500
To: omitted@earthlink.net
Subject: Reply to thread 'For sale: LS6 intake, Shaner TB, Grotyohann headers'
From: "CamaroZ28.Com Message Board" <admin@camaroz28.com>
Auto-Submitted: auto-generated
Message-ID: <20090103162543.3579c7571036@www.camaroz28.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 8bit
X-Priority: 3
X-Mailer: vBulletin Mail via PHP
X-ELNK-Received-Info: spv=0;
X-ELNK-AV: 0
X-ELNK-Info: sbv=0; sbrc=.0; sbf=0b; sbw=000;
---

SMTP header from second notification:
---
Status: U
Return-Path: <admin@camaroz28.com>
Received: from mx-pigeons.atl.sa.earthlink.net ([127.0.0.1])
by mx-pigeons.atl.sa.earthlink.net (EarthLink SMTP Server) with SMTP id 1lj9jQ45f3Nl34g1; Sat, 3 Jan 2009 11:25:46 -0500 (EST)
Received: from ns.camaroz28.com ([64.65.56.121])
by mx-pigeons.atl.sa.earthlink.net (EarthLink SMTP Server) with ESMTP id 1lj9jQ53y3Nl34g0
for <omitted@earthlink.net>; Sat, 3 Jan 2009 11:25:46 -0500 (EST)
Received: (qmail 10634 invoked by uid 48); 3 Jan 2009 11:25:46 -0500
Date: 3 Jan 2009 11:25:46 -0500
To: omitted@earthlink.net
Subject: Reply to thread 'For sale: LS6 intake, Shaner TB, Grotyohann headers'
From: "CamaroZ28.Com Message Board" <admin@camaroz28.com>
Auto-Submitted: auto-generated
Message-ID: <20090103162543.3579c7571036@www.camaroz28.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 8bit
X-Priority: 3
X-Mailer: vBulletin Mail via PHP
X-ELNK-Received-Info: spv=0;
X-ELNK-AV: 0
X-ELNK-Info: sbv=0; sbrc=.0; sbf=0b; sbw=000;
---

I'm also receiving duplicate PM notifications.