I have a CentOS 6.x 64bit Xen VM running on a static public IP address with no NAT,Proxy,FunnyBusiness. System runs a couple of small websites using Apache Virtual Hosts and also runs Zimbra (sort of).

I have set everything up and had a successful install of Zimbra without much of an issue. I have installed my SSL cert, setup SPF record in DNS, and also a DKIM txt record (i think properly).

The problem is my email seems to go straight to Spam boxes on multiple services. I have checked and my IP and domain names aren't on any blacklists I can find, nor are they found in projecthoneypot.org.

I sent a test email to a Gmail account from the webmail on Zimbra. This is the Header as-seen from the Gmail recipient:

Code:
Delivered-To: test@gmail.com
Received: by 10.220.60.197 with SMTP id q5csp157176vch;
        Tue, 18 Jun 2013 18:05:42 -0700 (PDT)
X-Received: by 10.49.109.72 with SMTP id hq8mr491858qeb.38.1371603941449;
        Tue, 18 Jun 2013 18:05:41 -0700 (PDT)
Return-Path: <jason@test.com>
Received: from mail.test.net ([174.xxx.xxx.xxx])
        by mx.google.com with ESMTP id ht6si17143078qab.112.2013.06.18.18.05.39
        for <test@gmail.com>;
        Tue, 18 Jun 2013 18:05:39 -0700 (PDT)
Received-SPF: pass (google.com: domain of jason@test.com designates 174.xxx.xxx.xxx as permitted sender) client-ip=174.xxx.xxx.xxx;
Authentication-Results: mx.google.com;
       spf=pass (google.com: domain of jason@test.com designates 174.xxx.xxx.xxx as permitted sender) smtp.mail=jason@test.com;
       dkim=neutral (bad format) header.i=@test.com
Received: from localhost (localhost.localdomain [127.0.0.1])
	by mail.test.net (Postfix) with ESMTP id BD3EE10E95C
	for <test@gmail.com>; Wed, 19 Jun 2013 01:05:38 +0000 (UTC)
Received: from mail.test.net ([127.0.0.1])
	by localhost (mail.test.net [127.0.0.1]) (amavisd-new, port 10032)
	with ESMTP id NtksLUoaRMRj for <test@gmail.com>;
	Wed, 19 Jun 2013 01:05:33 +0000 (UTC)
Received: from localhost (localhost.localdomain [127.0.0.1])
	by mail.test.net (Postfix) with ESMTP id CE01310E960
	for <test@gmail.com>; Wed, 19 Jun 2013 01:05:32 +0000 (UTC)
DKIM-Filter: OpenDKIM Filter v2.8.0 mail.test.net CE01310E960
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=test.com;
	s=EF718F68-D7DB-11E2-8412-A83791C66FFE; t=1371603932;
	bh=g3zLYH4xKxcPrHOD18z9YfpQcnk/GaJedfustWU5uGs=;
	h=Date:From:To:Message-ID:Subject:MIME-Version:Content-Type:
	 Content-Transfer-Encoding;
	b=fXd8vGZQHI0vBGbvSCzBmylfo2Jadh5UCi222KLfaDpWRZh/4/AlbGlrhEYdTfD2U
	 X2oUTCwR/mbLqSQr/d7wDswt32HWU6DRhsJ6PeeBDOMih8+tuJn//+cE00f/CuXetp
	 k9GnvZ4j+BGKAdusKAZUoIhElKagRDNuY6Tj5IHo=
X-Virus-Scanned: amavisd-new at test.net
Received: from mail.test.net ([127.0.0.1])
	by localhost (mail.test.net [127.0.0.1]) (amavisd-new, port 10026)
	with ESMTP id DwxvkYd09CwQ for <test@gmail.com>;
	Wed, 19 Jun 2013 01:05:32 +0000 (UTC)
Received: from mail.test.net (www.test.com [174.xxx.xxx.xxx])
	by mail.test.net (Postfix) with ESMTP id 0923110E95C
	for <test@gmail.com>; Wed, 19 Jun 2013 01:05:32 +0000 (UTC)
Date: Wed, 19 Jun 2013 01:05:31 +0000 (UTC)
From: Jason S. <jason@test.com>
To: test@gmail.com
Message-ID: <2023202761.24.1371603931731.JavaMail.zimbra@test.com>
Subject: test
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
X-Originating-IP: [98.244.35.232]
X-Mailer: Zimbra 8.0.4_GA_5737 (ZimbraWebClient - GC27 (Win)/8.0.4_GA_5737)
Thread-Topic: test
Thread-Index: 8fHVV3QJizsIglcT6jGzgyJ/nsiOOA==
I'm not sure what other details to provide, please ask if needed. If you would like me to send you a test email, or personal domain info such as real domain name, etc, please PM me but post advice here so others can follow/learn.

I would appreciate any assistance or advice.