change default "true" / "false" values of a checkbox after form submiting

I would love to get rid of the standard "true" or "false" value of a checkbox when it is checked / unchecked and sent through a form... I wrote this little script but can't make it working, I am obviousliy new to code :)

In short: for a checked checkbox, instead of "true" I would love to have "Réservé" and instead of "false" I would love to have "Non Réservé"... is that possible ?

Have a look at my jsfiddle if you want:

http://jsfiddle.net/anthonysalamin/JySSN/207/

jquery

// wait for DOM to be ready
$(document).ready(function() {

  //define the variable for the checkboxes on the page
  var allCheckboxes = $("input:checkbox[class=outsider]");

  //calls the append function on form submission
  $("#form-element").submit(function(event) {

    $(allCheckboxes).on('click', function() {

    $(this).val(this.checked ? Réservé : Non Réservé);

      alert($(this).val()); 
      event.preventDefault();
    });
  });
});

HTML

<form id="form-element">
  <input type="checkbox" class="outsider" />
  <input type="submit" value="Send" data-wait="Wait..." />
</form>