function locale_block($op = 'list', $delta = 0) {
  if ($op == 'list') {
    $block[0]['info'] = t('Language switcher');
    // Not worth caching.
    $block[0]['cache'] = BLOCK_NO_CACHE;
    return $block;
  }

  // Only show if we have at least two languages and language dependent
  // web addresses, so we can actually link to other language versions.
  elseif ($op == 'view' && variable_get('language_count', 1) > 1 && variable_get('language_negotiation', LANGUAGE_NEGOTIATION_NONE) != LANGUAGE_NEGOTIATION_NONE) {
    $languages = language_list('enabled');
    foreach ($languages[1] as $language) {
      $links[$language->language] = array(
        'href'       => $_GET['q'],
        'title'      => $language->native,
        'language'   => $language,
        'attributes' => array('class' => 'language-link'),
      );
    }

    drupal_alter('translation_link', $links, $_GET['q']);
    $options=array();
    foreach ($links as $langcode => $link) {
      $options[$langcode]=$link['title'];
    }

    $block['subject'] = t('Languages');
    $block['content'] = drupal_get_form('locale_block_form', $options);
    return $block;
  }
}

function locale_block_form(&$form_state,$options){
  drupal_add_js(drupal_get_path('module', 'locale') .'/locale.js', 'module');
  global $language;
  $form['language'] = array (
    '#type'    => 'select',
    '#options' => $options,
    '#default_value' => $language->language,
  );
  $form['submit_language'] = array(
    '#type'  => 'submit',
    '#value' => t('Change')
  );

  return $form;
}
function locale_block_form_submit($form, &$form_state) {
  $languages = language_list('enabled');

  $links = array();
  foreach ($languages[1] as $language) {
    $links[$language->language] = array(
        'href'       => $_GET['q'],
        'language'   => $language,
    );
  }
  drupal_alter('translation_link', $links, $_GET['q']);

  $langcode=$form_state['values']['language'];
  if (isset($links[$langcode])) {
      $links[$langcode]['absolute']=true;
      $goto=url($links[$langcode]['href'] ,$links[$langcode]);
  }
  $form_state['redirect'] = $goto;
}