Okay I took it to a new level and sniffed the outgoing smtp session to see if it made it into google's server:
tcpdump -l -s0 -w - tcp dst port 25 | strings
It looks like it is sending it out so I'm not sure what gives:
JEHLO mail.mydomain.com
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cMAIL FROM: SIZE=1755
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zRCPT TO:
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DATA
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0Received: from mail-lb0-f181.google.com (mail-lb0-f181.google.com [209.85.217.181])
by mail.mydomain.com (Postfix) with ESMTP id 6641FE19F6
for ; Mon, 30 Dec 2013 14:20:49 -0500 (EST)
Authentication-Results: mail.mydomain.com; dkim=pass
reason="2048-bit key; insecure key"
header.d=gmail.com header.i=@gmail.com header.b=mxTtCKp6;
dkim-adsp=pass; dkim-atps=neutral
Received: by mail-lb0-f181.google.com with SMTP id q8so5827277lbi.12
for ; Mon, 30 Dec 2013 11:20:48 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=gmail.com; s=20120113;
h=mime-version:date:message-id:subject:from:to:content-type;
bh=ppUKk8ESYlJZsRuZ0cEXf7GqUyAxDklN/LCG1aC8bgk=;
b=mxTtCKp60FlT0FvNYDXdydHo8+bt7tjZKA59wKnEaE4zcSNUA56A2ONazXPLCv77eD
kGXIp4I7HKICKkqSlmm9janyhJZFzMSwm0yNggItnBLgwuT5Yy38qc0I2WL2FxC2hZgc
FDl56rFU3780tLG4qnqbVuO9rp+S0g42zBYPVrK8tU6+ZXXMJEk268FFbUHemWPyO9ra
ytGmrloaqYtVknJXtwepqM2lfc5BIYUANMQQTHnlEpYwPg6dcEvPgE4CXb95xZ58Wz5p
+dA7vrc6ctUQgP+0hmyGab2RcKl14zeg70xkoJPdt1kdS13kQaM75HZ03zvuBSAhgcg/
p46w==
MIME-Version: 1.0
X-Received: by 10.112.12.229 with SMTP id b5mr585009lbc.90.1388431248317; Mon,
30 Dec 2013 11:20:48 -0800 (PST)
Received: by 10.112.214.134 with HTTP; Mon, 30 Dec 2013 11:20:48 -0800 (PST)
Date: Mon, 30 Dec 2013 13:20:48 -0
UTJ}
0600
Message-ID:
Subject: s
From: Michael Johnson
To: me@mydomain.com
Content-Type: multipart/alternative; boundary=001a11c39c4659e35404eec557a9
--001a11c39c4659e35404eec557a9
Content-Type: text/plain; charset=ISO-8859-1
--001a11c39c4659e35404eec557a9
Content-Type: text/html; charset=ISO-8859-1
--001a11c39c4659e35404eec557a9--
UTJ}
^QUIT
UTJ}
UTJ}