title: IE9 "no transport" error, Firefox/Chrome work, and the request is not cross-site
body: <p>I'm making a standard JQuery .ajax call, already jumped through hoops to get it working in other browsers but now I'm just stuck on IE9 (and lower, I'm sure). The page canada.example.com/registration contains a registration form, which is submitted using JQuery's .ajax:</p>
  
  <pre><code>jQuery.ajax({
      url: 'http://canada.example.com/registration.php',
      type: 'POST'
  });
  </code></pre>
  
  <p>Note the POST request is made to <a href="http://canada.example.com/registration.php">http://canada.example.com/registration.php</a>, so I'm not making a cross-site request.</p>
  
  <p>This now works in Firefox and Chrome, but IE9 returns a "No transport" error like it didn't try to make the request. Any ideas on how to fix this? I've gone to some lengths to try and make this not a cross-origin request, but IE 9 still seems to think it is.</p>