For the language filter from WPML to take effect you have to allow filters in get_posts. Default this is off.

You can add `suppress_filters=0` to your get_posts args and it should work. See: http://codex.wordpress.org/Template_Tags/get_posts#Parameters

    <ul id="archive-list">
        <?php $args = array( 'suppress_filters' => 0, 'numberposts' => '-1', 'post_type' => 'post', );
        $myposts = get_posts($args);
        foreach($myposts as $post) : ?>
        <li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
        <?php endforeach; ?>
    </ul>