jQuery.ajaxSetup({ 
  "beforeSend": function(xhr) {xhr.setRequestHeader("Accept", "text/javascript")} 
})

jQuery.fn.submitWithAjax = function() {
  this.submit(function() {
    $.post(this.action, $(this).serialize(), null, "script");
    return false;
  })
  return this;
};

$(document).ready(function() {
  $("#new_email").submitWithAjax();
})