title: jQuery Validate plugin and a default input value not working
body: <p>I have a form which has default values set, which should be treated as "empty fields".
  I did see another post on this subject, but have not been able to get anything to work so far.
  It still only throws the error when the field is empty, but should do so when it has its "default value" as well.</p>
  
  <p>Here is the code with a simple single field form:</p>
  
  <hr>
  
  <pre><code>&lt;title&gt;Untitled Document&lt;/title&gt;
  &lt;form name="contactInfo" action="##" method="post" enctype="multipart/form-data"&gt;
  &lt;div class="step"&gt;
  &lt;div style="float:left; width:45%;"&gt;
  &lt;input type="text" name="email" value="enter your email" tabindex="1" 
  onClick="this.select();" required defaultInvalid /&gt;
  &lt;/div&gt;
  &lt;/div&gt;
  &lt;input type="submit" /&gt;
  &lt;/form&gt;
  &lt;!--- form validation to handle non blank default fields ---&gt;
  &lt;script language="javascript" type="text/javascript"&gt;
  $().ready(function() {
    jQuery.validator.addMethod("defaultInvalid", function(value, element) 
          {
              switch (element.value) 
              {
                  case "enter your email":
                      if (element.name == "email") return false;
                      break;
                  default: return true; 
                      break;
              }
          });
       // validate the comment form when it is submitted
      $("#contactInfo").validate(
      {
        rules: 
        {
         email: "required defaultInvalid"
        },
        messages: 
        {
         email: "Please input your email."
        }
      });
  });
  &lt;/script&gt;
  </code></pre>
  
  <hr>
  
  <p>Two issues:</p>
  
  <ol>
  <li>it only triggers validation error when empty (instead of when having default value)</li>
  <li>the custom message I've added does not display.</li>
  </ol>
  
  <p>I've searched stackOverflow and the web for a good hour without any luck finding a solution.</p>