date validate

date validate

Hi,

i have form with several fields, but her is one of an example that would like to do.  if i click on name field, the text box for completed_date is enable but it's not really required or check for validate date.
How can only validate this field is defined and invalid entered?

<script type="text/javascript">
    $(document).ready(function() {
       
        $("#form").validate();
               
    });
    </script>
    <input type="text" name="name"  id="name" class="required" title="Name is required." onkeyup="EnableTextBox(this, 'completed_date', 1)"/>
     <input type="text" name="completed_date" class="required date" title="Completed is required."  value="" />








 
thank you,