GMail parece ignorar Responder para

Estou usando uma conta do Gmail para enviar e-mails do meu site. Estou usando a mesma conta para receber e-mails gerados pelo serviço de contato no meu site.

Estou usando o campo Responder para, para tentar facilitar a resposta e retornar facilmente às pessoas.

A mensagem aparece com o endereço 'de' e ignora o endereço 'resposta a'.

Aqui está o meu cabeçalho:

Return-Path: <info@rds.com>
Received: from svr1 (ec2-79-125-266-266.eu-west-1.compute.amazonaws.com [79.125.266.266])
    by mx.google.com with ESMTPS id u14sm23273123gvf.17.2010.03.10.14.33.24
    (version=TLSv1/SSLv3 cipher=RC4-MD5);
    Wed, 10 Mar 2010 14:33:25 -0800 (PST)
Received: from localhost ([127.0.0.1] helo=www.rds.com)
by aquacouture with esmtp (Exim 4.69)
(envelope-from <info@rds.com>)
id 1NpUSx-0001dK-JM
for info@rds.com; Wed, 10 Mar 2010 22:33:23 +0000
User-Agent: CodeIgniter
Date: Wed, 10 Mar 2010 22:33:23 +0000
From: "New Inquiry" <info@rds.com>
Reply-To: "Beren" <me@gmail.com>
To: info@rds.com
Subject: =?utf-8?Q?Test?=
X-Sender: info@rds.com
X-Mailer: CodeIgniter
X-Priority: 3 (Normal)
Message-ID: <4b981e3390391@rds.com>
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="B_ALT_4b981e3390ccd"

This is a multi-part message in MIME format.
Your email application may not support this format.

--B_ALT_4b981e3390ccd
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit

test


--B_ALT_4b981e3390ccd
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: quoted-printable

test

--B_ALT_4b981e3390ccd--