Hello friends!

Friends, I tried a lot of changes, but no success to send the email correctly formated, I'm using the same domain to send mail and the email pass trough spf and authentication, but has been marked as spam for some accounts using gmail ou google app's.

The header's are:

    Delivered-To: [email protected]
Received: by 10.231.208.5 with SMTP id ga5cs194453ibb;
        Mon, 17 Jan 2011 11:08:33 -0800 (PST)
Received: by 10.142.213.18 with SMTP id l18mr4141524wfg.192.1295291312735;
        Mon, 17 Jan 2011 11:08:32 -0800 (PST)
Return-Path: <[email protected]>
Received: from hm1315-29.locaweb.com.br (hm1315-29.locaweb.com.br [201.76.49.185])
        by mx.google.com with ESMTP id a70si8528144yhd.33.2011.01.17.11.08.32;
        Mon, 17 Jan 2011 11:08:32 -0800 (PST)
Received-SPF: pass (google.com: domain of [email protected] designates 201.76.49.185 as permitted sender) client-ip=201.76.49.185;
Authentication-Results: mx.google.com; spf=pass (google.com: domain of [email protected] designates 201.76.49.185 as permitted sender) [email protected]
Received: from hm1974.locaweb.com.br (189.126.112.86) by hm1315-38.locaweb.com.br (PowerMTA(TM) v3.5r15) id h6i9r00nvfo8 for <[email protected]>; Mon, 17 Jan 2011 17:08:31 -0200 (envelope-from <[email protected]>)
X-Spam-Status:  No
Received: from bart0020.locaweb.com.br (bart0020.email.locaweb.com.br [200.234.210.22])
    by hm1974.locaweb.com.br (Postfix) with ESMTP id 9C03511E00B5;
    Mon, 17 Jan 2011 17:08:31 -0200 (BRST)
X-LocaWeb-COR: locaweb_2009_x-mail
Received: from admin.domain.com.br (hm686.locaweb.com.br [200.234.200.116])
    (Authenticated sender: [email protected])
    by bart0020.locaweb.com.br (Postfix) with ESMTPA id 4B2F08CAFD6B;
    Mon, 17 Jan 2011 17:08:31 -0200 (BRST)
Message-ID: <[email protected]>
Date: Mon, 17 Jan 2011 17:08:31 -0200
Subject: Domain - Assunto
From: Sistema <[email protected]>
Reply-To: rodrigo <[email protected]>
To: balucia <[email protected]>
MIME-Version: 1.0
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: quoted-printable
X-Virus-Scanned: clamav-milter 0.96.5 at hm1974
X-Virus-Status: Clean

This header has been marked as spam, I had no more ideas how to fix it and there are people borrowing me about this.

Thanks and best regard's.