function helper_menu() {
  $items['test'] = array(
    'title' => 'test',
    'page callback' => 'helper_page_forms',
    'access arguments' => array('access content'),
  );
  return $items;
}

function helper_page_forms() {
  $build['form1'] = drupal_get_form('helper_form1');
  $build['form2'] = drupal_get_form('helper_form2');
  return $build;
}

function helper_form1($form, &$form_state) {
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit 1',
    '#ajax' => array(
      'callback' => 'helper_form1_ajax',
    ),
  );
  return $form;
}

function helper_form2($form, &$form_state) {
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit 2',
    '#ajax' => array(
      'callback' => 'helper_form2_ajax',
    ),
  );
  return $form;
}

function helper_form1_ajax() {
  return array(
    '#type' => 'ajax',
    '#commands' => array(
      ajax_command_alert('ajax 1'),
    ),
  );
}

function helper_form2_ajax() {
  return array(
    '#type' => 'ajax',
    '#commands' => array(
      ajax_command_alert('ajax 2'),
    ),
  );
}