get_posts not working properly

This snippet inside a PHP code widget returns 7 links to the same post.
Outside the widget (directly executed for example in a custom template), works properly and returns 7 different posts:

<ul>
<?php
$args = array( 'posts_per_page' => 7, 'category' => 9 );
$tag_posts = get_posts( $args ); foreach ( $tag_posts as $post ) : setup_postdata( $post ); ?>
	<li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
<?php endforeach; wp_reset_postdata(); ?>
</ul>

http://wordpress.org/plugins/php-code-widget/