Event.observe(window, 'load', init, false);

function init() {
  Event.observe('signup', 'submit', storeAddress);
}

function storeAddress(e) {
  $('response').innerHTML = 'Adding your email address...';
  var pars = 'email=' + escape($F('email'));
  var myAjax = new Ajax.Updater('response', 'ajaxServer.php', {method: 'get', parameters: pars});
  Event.stop(e);
}