title: SMTP: Error 554, message is not RFC compliant
body: <p>Our custom automatic email delivery service is hitting this problem with a couple of our clients' SMTP servers. It only happens with about three of them--the message is bounced back with the following response from the SMTP server:</p>
  
  <pre><code>SMTP error from remote mail server after end of data:
  host clients.host.name [XXX.XXX.XXX.XXX]: 554 Message is not RFC compliant
  </code></pre>
  
  <p>Here's the email header generated by our custom application. Note that our own emails go through without any problems, but our application's don't.</p>
  
  <pre><code>Return-path: &lt;ouremail@our.domain&gt;
  Received: from [XXX.XXX.XXX.XXX] (helo=our.stmp.server)
  by clients.smtp.server with smtp (Exim 4.69)
  (envelope-from &lt;ouremail@our.domain&gt;)
  id 1LQNiv-0008MM-IM
  for clientsaddress@clients.domain; Fri, 23 Jan 2009 13:13:33 -0200
  Subject: Test Mail
  From: &lt;ouremail@our.domain&gt;
  To: &lt;clientsaddress@clients.domain&gt;
  MIME-Version: 1.0
  X-Priority: 3 (Normal)
  X-MSMail-Priority: Normal
  X-Mailer: ourCompany (ourcompanys.web.site)
  Importance: Normal
  Content-Type: multipart/mixed;
  boundary="OURCOMPANYSsoftsmtp123X4560102897C"
  X-Scan-Signature: e932e7231c8991cb29810b36327eaa17
  
  
  --OURCOMPANYSsoftstmp123X4560102897C
  Content-Type: text/plain;
  charset="iso-8859-1"
  Content-Transfer-Encoding: base64
  
  BASE64ENCODING
  
  --OURCOMPANYSsoftstmp123X4560102897C--
  </code></pre>
  
  <p>Any ideas?</p>