title: onclick on input type image causes form submit
body: <p><strong>Scenario</strong></p>
  
  <p>I have got this form:</p>
  
  <pre><code>&lt;form action="EditShippingInfo.asp" method="POST" id="frmShippingInfo"&gt;
    &lt;!-- stuff --&gt;
    &lt;input type="image" id="EditShippingInfo" onclick="javascript:checkShippingInfo(this.form);" src="/img/btn_save.gif" /&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>The <code>checkShippingInfo</code> function runs some input validation control. Eventually it runs a server side control via AJAX:</p>
  
  <pre><code>  function checkShippingInfo(form){
          /* runs validation controls */
  
          var data = setDataForAjax;
          $.ajax({
              type: 'GET',
              url: '/include/checkAddresses.asp',
              data: data,
              async: false,
              success: function (m) {
                  if (m == 0) {
                      /* I want to run form.submit only if m=0 */
                      form.submit();
                  }
                  else {
                      /* otherways I display a message */
                      alert(m);
                      return false;
                  }
              }
          });
    }
  </code></pre>
  
  <p>But the form submit is triggered <strong>anyway</strong>, even if m!=0.</p>
  
  <p><strong>Question</strong></p>
  
  <p>I want to trigger the <code>form.submit</code> only under a certain condition.
  Does <code>input type="image"</code> trigger a submit in anycase?</p>