ajax_defaults.js

  var spinner = $('#ajax-spinner');
  $(document).ajaxSend(function() {
    $('input[type=submit]').attr('disabled', 'disabled');
    $('#warningBox').hide();
    spinner.show()
  }).ajaxStop(function() {
    $('input[type=submit]').removeAttr('disabled');
    spinner.hide()
  });
  
  $("form").submit(function(){
    $('input[type=submit]').attr('disabled', 'disabled');
    return true;
  });