<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-2.1.3.min.js"></script>
  <script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.13.0/jquery.validate.min.js"></script>
  <script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.13.0/additional-methods.min.js"></script>



  <script type="text/javascript">
    $(function(){
  $("#validacija").validate({
    rules: {
      username:{
        required: true,
        minlength: 6
      },
      password: {
        required: true,
        minlength: 7
      }

    },
    messages:{
      username:{
        required: 'Unesite korisničko ime',
        minlength: 'Korisničko ime mora da sadrži bar 6 karaktera'
      },
      password:{
        required: 'Unesite šifru',
        minlength: 'Šifra mora da sadrži bar 7 karaktera'
      }
    }
  });

});
  </script>