I am having problems with `pagination` on `category` page that lists posts only within a certain category. Here is my code:

What happens is the `Next` link takes to `/page/2` but the content stays the same.

```
<?php
    $id = get_cat_id($current_category);
    $my_query = new WP_Query('cat='. $id .'&showposts=2');
    while ($my_query->have_posts()) : $my_query->the_post();
?>
    <?php the_content( __( 'Continue reading <span class="meta-nav">&rarr;</span>', 'themename' ) ); ?> 
    <?php endif; ?>
<?php endwhile; ?>

<?php if (  $my_query->max_num_pages > 1 ) : ?>
    <nav id="nav-below">
        <div class="next"><?php previous_posts_link( __( '<span></span> Previous ', 'themename' ) ); ?></div>
        <div class="prev"><?php next_posts_link( __( 'Next <span></span>', 'themename' ) ); ?></div>
    </nav>
<?php endif; ?>

```