Yahoo Mail is sending our server's transactional emails to the Spam folder, even though we have taken quite a few anti-spam steps. By contrast, Gmail allows the messages through to the inbox just fine. Here are the things which are in place:

1. SPF is set up for the domain holsteinplaza.com. Yahoo reports spf=pass in the message headers.

2. DKIM is set up for the domain holsteinplaza.com. Yahoo reports dkim=pass in the message headers.

3. We have a proper reverse DNS entry for the sending mail server. Name -> IP matches IP -> Name.

4. Neither Domainkeys nor SenderID are set up. From what I can tell, DKIM is the way of the future, and there is not much to be gained from adding Domainkeys or SenderID.

Following are the headers. Any ideas what more I should do to get Yahoo to stop flagging the emails as spam?

From Holstein Plaza Auctions Sat Jun 25 18:30:08 2011
X-Apparently-To: [email protected] via 98.138.90.132; Sat, 25 Jun 2011 18:30:11 -0700
Return-Path: <[email protected]>
X-YahooFilteredBulk: 70.32.113.42
Received-SPF: pass (domain of holsteinplaza.com designates 70.32.113.42 as permitted sender)
X-YMailISG: i_vaA_QWLDuLOmXhDjUv3aBKJl5Un6EiP6Yk2m4yn3jeEuYK
 MkhpqIt9zDUbHARCwXrhl9pqjTANurGVca7gytSs.mryWVQcbWBx.DaItWRb
 VcyrIzwMzXKCSeu06H2a.cJ7HG5vJLJaKmHUUI_1ttXKn_Aegiu5yHvFX83R
 Lpth0witO9zfaKvOMaJV3LAxpIpFOydwvq1cqjZ8nURxQbxM3Cl.QW7MxxrC
 09qLVn_D_xSdU94QdU22IsVmlaRHv.uU5dnIazu.KSkhKpYykDoZA2SH0SY4
 JmTZj3LP8N926xXVDzYQ5K6QvKuJL5g0d9pYZx3KC59sgIu5oHlJ3Q15RdKb
 f3OJw0PR6oIyJ2yStVr8vfbDgOfj3qig03.Tw6g6MMNpv1G7Cuol4oJeUaYP
 xELxX6dHgBgCSuWMcbsrxbK4BIXcS2qhpMqYQ4Isk.XXyA8uvmFXyvgc1ds5
 8jo0rW.Wsw.55Z.KTPaQ0gHXj0T3OGppYMELSJv1iuhPyyAnZpmq01CU0Qd5
 CcRgdyW3HaqhmpXqJCS0Clo16zXA4HmAjR0tgIQrHRLc3D9N02AOzvmDgCb1
 vCh0p00QeKVq8UNkcShPRxZFKi9khtkLhPBlXEKkhJ76zyDmHUxTY.dQHVVD
 8D2hx7BxbqI9DINI8x5oR5Q8hYkZqHYQsmGNkaU77O2BnsEv5WxMEmzrBJ4Z
 h8zGCidgYPiZycZfnfaBp0Xb4tya2WMTN45W02JFcO1qq_UMJ9xPeqZhPEj.
 j9YvBAC8324GGF.c8eWcNB2VB34QHgTcVUl3.c0XUCuncls9Cyg4L7AoIdCi
 HvAklSzDDu9nW6732VEipV9FJ_JkDupDNQU2hfiPG.3OeF8GwTnVYnEn0EiZ
 aO0NCnZhXuLDcN3K7ml3846yRdASvzPFs9s4aJkzR0FkhVvptiMBEOdRkKdG
 wHWmvWpK4GTZpW4yU7CnKpW2MiWWn1MP0h_CCZFKs5.3mfmfPjPVIABN_RuU
 Q8ex5hdKnKlQiqK56LzcPRnYmNtrwdsUX9CYn9d6cPpXR_Bi5jrNJMNzdFvq
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 HhDItpHhDxKRUscM28IR.exetq4QCzyM
X-Originating-IP: [70.32.113.42]
Authentication-Results: mta1267.mail.ac4.yahoo.com  from=holsteinplaza.com; domainkeys=neutral (no sig);  from=holsteinplaza.com; dkim=pass (ok)
Received: from 127.0.0.1  (EHLO predator.axis80.com) (70.32.113.42)
  by mta1267.mail.ac4.yahoo.com with SMTP; Sat, 25 Jun 2011 18:30:11 -0700
Received: (qmail 1440 invoked by uid 48); 25 Jun 2011 21:30:09 -0400
To: [email protected]
Subject: this is a test
X-PHPMAILER-DKIM: phpmailer.worxware.com
DKIM-Signature: v=1; a=rsa-sha1; q=dns/txt; l=203; s=auction;
    t=1309051808; c=relaxed/simple;
    h=From:To:Subject;
    d=holsteinplaza.com; [email protected];
    z=From:=20Holstein=20Plaza=20Auctions=20<[email protected]>
    |To:[email protected]
    |Subject:=20this=20is=20a=20test;
    bh=B3Tw5AQb1va627KEoazuFEBZ0fg=;
    b=oQ5uFq+oekPTGhszyIritjuuIAi3qPNyeitu+aWMhdx3oC6O2j5hJsDFpK0sS5fms7QdnBkBcEzT0iekEvn9EfAdCkGZ2KrtEC0yv7QKQcrjXxy07GJpj9nq0LYbgOuPdw8mGvKxlRZ+jFBX0DRJm0xXFLkr+MEaILw7adHTCCM=
Date: Sat, 25 Jun 2011 21:30:08 -0400
From: Holstein Plaza Auctions <[email protected]>
Reply-to: Holstein Plaza Auctions <[email protected]>
Message-ID: <[email protected]>
X-Priority: 3
X-Mailer: PHPMailer 5.1 (phpmailer.sourceforge.net)
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="iso-8859-1"
Content-Length: 195