http://mxtoolbox.com/SuperTool.aspx?action=smtp%3asatanninja.com&run=toolpagedns reverse record mismatch. email servers are very painful to setup. exim is good about not being too absurd to wrap your head around. my technique to test email servers involves re-sending conformation emails to my self & looking @ /var/log/messages or /var/log/exim/faillog id not touch the server configuration, and work on the dns records.
spf & dkim are good.
Received: from satanninja.com (satanninja.com. [129.121.189.45])
by mx.google.com with ESMTPS id n6si1800970ige.22.2014.05.09.20.44.42
for my@email.com
(version=TLSv1 cipher=RC4-SHA bits=128/128);
Fri, 09 May 2014 20:44:43 -0700 (PDT)
Received-SPF: pass (google.com: domain of noreply@satanninja.com designates 129.121.189.45 as permitted sender) client-ip=129.121.189.45;
Authentication-Results: mx.google.com;
spf=pass (google.com: domain of noreply@satanninja.com designates 129.121.189.45 as permitted sender) smtp.mail=noreply@satanninja.com;
dkim=pass header.i=@satanninja.com
Message-Id: <536da0ab.8614320a.7241.ffffb09fSMTPIN_ADDED_MISSING@mx.google.com>
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=satanninja.com; s=default;
h=Content-Transfer-Encoding:Content-Type:Mime-Version:Date:From:To:Subject; bh=rJQ3i9eVMdtpT7kxegl+fRUnGowflV0f+pIZHsONv4A=;
b=ynxSEdwvLeOZueF3B8XEJ4xSTmCgaky+OLGxwI7WS3LqLrZLAD5Y8FsyNBRmICQ7hteMQbGQByILj6HpScxYL9oNgu6/RX1nTFJl2V0m5NCOoUMcxA5TTh4anQl76mQsoJgmWa2a+7zOZ9lLuwz+fbDXyXb86BPPJVRVN+J23KI=;
Received: from satanninja.com ([129.121.189.45]:59368 helo=ssl://satanninja.com)
by host.calebd.net with esmtpsa (TLSv1:DHE-RSA-AES256-SHA:256)
(Exim 4.82)
(envelope-from <noreply@satanninja.com>)
id 1WiyDK-0000br-A9