title: hidden fields in IE are considered disabled?
body: <p>With the below sample page I get a different output for IE than I do for other browsers. </p>
  
  <pre><code>&lt;html&gt;
  &lt;head&gt;
      &lt;title&gt;hidden fields test&lt;/title&gt;
      &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js" type="text/javascript"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;form&gt;
          &lt;input type="hidden" value="hidden1" /&gt;
          &lt;input type="hidden" value="hidden2" /&gt;
          &lt;input type="text" value="text1" /&gt;
          &lt;input type="text" value="text2" /&gt;
      &lt;/form&gt;
      &lt;script type="text/javascript"&gt;
          $(function() {
              var inputs = $("form input:enabled");
              var concatenated = '';
              inputs.each(function() {
                  concatenated = concatenated + $(this).val();
              });
  
              alert(concatenated);
          });
      &lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>With IE 8 (8.0.7600.16385), the output is "text1text2", with Chrome (10.0.648.127) and Firefox (3.6.13) it is "hidden1hidden2text1text2". This was unexpected to me. Is this a bug in IE or jQuery, or just an expected difference in browsers that jQuery is not accounting for?  </p>
  
  <p>Do hidden fields in IE always carry an implicit "disabled"?</p>