I did this and worked very well for me. The only problem is that you have to save the post an then the meta box appear.
$post_id = $_GET['post'] ? $_GET['post'] : $_POST['post_ID'];
$template_file = get_post_meta($post_id, '_wp_page_template', TRUE);
if ($template_file == 'template-quienessomos.php') {
ot_register_meta_box( $quienessomos_meta_box );
}