I know that this question is very popular, but I really hope that somebody can help me.
Message headers:

Delivered-To: ss@ss.ss
Received: by 10.216.42.7 with SMTP id i7csp410722web;
        Tue, 23 Oct 2012 15:15:37 -0700 (PDT)
Received: by 10.14.203.132 with SMTP id f4mr18989899eeo.11.1351030537206;
        Tue, 23 Oct 2012 15:15:37 -0700 (PDT)
Return-Path: <master@mydomain.test>
Received: from mydomain.test (mydomain.test. [178.79.180.***])
        by mx.google.com with ESMTP id j5si587844eeo.122.2012.10.23.15.15.36;
        Tue, 23 Oct 2012 15:15:37 -0700 (PDT)
Received-SPF: pass (google.com: domain of master@mydomain.test designates 178.79.180.*** as permitted sender) client-ip=178.79.180.***;
Authentication-Results: mx.google.com; spf=pass (google.com: domain of master@mydomain.test designates 178.79.180.*** as permitted sender) smtp.mail=master@mydomain.test; dkim=pass header.i=@mydomain.test
Received: by mydomain.test (Postfix, from userid 1000)
   id BD1713FDDD; Wed, 24 Oct 2012 02:15:36 +0400 (MSK)
X-DKIM: OpenDKIM Filter v2.5.2 mydomain.test BD1713FDDD
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mydomain.test;
   s=mydomain; t=1351030536;
   bh=7AFTz7yao7EUZcU2/wfS8rMYZgp2DlBpgu1XZm/z7Aw=;
   h=To:Subject:From:Reply-To:Date;
   b=mtPuv10jznUoOyqIxWDP/2e5MeOIJwbIYrN+pWyckLhGvosOdim+MCxw7sSnowt1t
    cTE8W51oJc70pZ7UPSqBAc1BYNoPoyjrZYl6IVqCQ4Bmwj12ukeiYjXTd0wufbHBVA
    +ZKs/19mS2F6RI5+ld4BEiv2lY+v4XJzeuDnRV/U=
To: ss@ss.ss
Subject: Ежедневный отчет о расходе ресурсов по услуге Scale Server
From: noreply@mydomain.test
Reply-To: noreply@mydomain.test
Mime-Version: 1.0
Content-Type: multipart/related; type="multipart/alternative"; boundary="=-fmc_rel_4087fe999af5ffe404e22aa5db26a412"
Message-Id: <20121023221536.BD1713FDDD@mydomain.test>

RDNS is looking to domain name. I've tried to send messages with php and with postfix smtp.

Any ideas?

Note.
When i've removed header

Content-Type: multipart/related; type="multipart/alternative"; boundary="=-fmc_rel_4087fe999af5ffe404e22aa5db26a412"

gmail shows unreadable message, but it hasn't gone to spam folder.

Does it mean that the problem with message content?

Have the recipients mark them as "Not Spam." GMail tends to shunt messages from unknown IP addresses into the Spam folder, and that is an effective way to train it.

_________________

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