mediawiki-translatedpages/TranslatedPages.alias.php

<?php

$messages = array();

$messages['en'] = array(
    'myextension' => 'Languages',
    'myextension-desc' => 'See the description',
    );

$messages['es'] = array(
    'myextension' => 'En otros idiomas',
    'addthis-desc' => 'Vease la descripción',
    );