title: jQuery Validate Plugin - Error messages not removed immediately after field becomes valid
body: <p>I'm trying to use the jQuery Validate plugin on a form like below:</p>
  
  <p>JS:</p>
  
  <pre><code>&lt;script src="jquery-1.7.1.js" type="text/javascript"&gt;&lt;/script&gt;
  &lt;script src="jquery.validate.js" type="text/javascript"&gt;&lt;/script&gt;
  &lt;script&gt;
  function ValidateFields() {
  
      $("#createProgramForm").validate({
          rules: {
              firstname: { required: true, minlength: 2 },
              lastname: { required: true }
          },
          messages: {
              firstname: { minlength: "Minimum 2 characters." },
              lastname: { required: "Please enter a last name." }
          }
      });
  
  
      if ($("#createProgramForm").valid()) {
          alert("Form is valid");
      }
  
  }
  &lt;/script&gt;
  </code></pre>
  
  <p>HTML:</p>
  
  <pre><code>&lt;body&gt;
  &lt;div id="page"&gt;
      &lt;form id="createProgramForm"&gt;
          &lt;p&gt;
              &lt;label for="firstname"&gt;
                  First Name&lt;/label&gt;
              &lt;input name="firstname" id="firstname" type="text" /&gt;
          &lt;/p&gt;
          &lt;p&gt;
              &lt;label for="lastname"&gt;First Name&lt;/label&gt;
              &lt;input name="lastname" id="lastname" type="text" /&gt;
          &lt;/p&gt;
          &lt;p&gt;
              &lt;button onclick="ValidateFields();"&gt;Validate&lt;/button&gt;
          &lt;/p&gt;
      &lt;/form&gt;
  &lt;/div&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>When I click Validate, the validation error messages are shown next to the fields. But the error messages don't go away once the field becomes valid like in the demo <a href="http://jquery.bassistance.de/validate/demo/" rel="nofollow">here</a>. Does anyone know why this happens?</p>