title: JQuery Validate checkbox row highlighting
body: <p>I am trying to validate multiple checkboxes with JQuery validate.  When less than 2 checkboxes are selected the row should be highlighted red, this works fine on the initial submssion and the user gets the error message with highlighted row or a tick if 2 or more are selected. </p>
  
  <p>The problem is when the user changes there initial choice.  I validate the form as the user moves  though it so if the selection changes from 2 to 1 the row no should re-highlight which it doesn't seem to do, although the error message does update.  Is there a way to add the error class back onto the row.</p>
  
  <pre><code>&lt;li id="li_bit001" class="radiocheck checkboxShowHide"&gt;
  &lt;h2 class="label"&gt;Required Check box&lt;/h2&gt;
  &lt;div&gt;
  &lt;span&gt;
  &lt;input name="chk_bit001" type="checkbox" id="chk_bit001" class="{required:true, minlength:2, messages:{required:'Please select atleast 2 checkbox'}}" /&gt;&lt;label for="chk_bit001" class="width-xs"&gt;Yes&lt;/label&gt;
  &lt;/span&gt;
  &lt;span&gt;  
  &lt;input name="chk_bit001" type="checkbox" id="chk_bit002" /&gt;&lt;label for="chk_bit002" class="width-xs"&gt;No&lt;/label&gt;
  &lt;/span&gt; 
  &lt;span&gt;
  &lt;input name="chk_bit001" type="checkbox" id="chk_bit003" /&gt;&lt;label for="chk_bit003" class="width-xs"&gt;Maybe&lt;/label&gt;
  &lt;/span&gt;
  &lt;span&gt;                  
  &lt;input name="chk_bit001" type="checkbox" id="chk_bit004" /&gt;&lt;label for="chk_bit004" class="width-xs"&gt;Whatever&lt;/label&gt;
  &lt;/span&gt;
  &lt;/div&gt;
  &lt;span class="errorlabel"&gt;&lt;/span&gt;
  &lt;/li&gt;
  
  $("#form1").validate({
  debug: true,
  highlight: function(element, errorClass) {
  $(element).closest('li').addClass('error-row');
  },
  unhighlight: function(element, errorClass) {
  $(element).closest('li').removeClass('error-row');  
  },
  submitHandler: function() { return false; },
  success: "valid",
  errorPlacement: function(error, element) {      
  error.appendTo(element.closest('li').find('.errorlabel'))}      
  });
  </code></pre>