show subpages recursively

gistfile1.txt

wpse13669_show_all_children( $post_id, $current_level ) {
    $children = get_posts( array(
        'post_type' =>'page',
        'posts_per_page' =>-1,
        'post_parent' => $post_id,
        'order_by' => 'title',
        'order' => 'ASC' ) );
    if ( empty($children) ) return;

    echo '<ul class="children level-'.$current_level.'-children">';

    foreach ($children as $child) {

        /* Here would be the point where you
            do whatever you want to display the 
            posts. The variable $current_level can
            be used if you want to style different 
            levels in the hierarchy differently */

            echo '<li>';

        echo '<a href="'.get_permalink($child->ID).'">';
        echo apply_filters( 'the_title', $child->post_title );
        echo '</a>';

        // now call the same function for child of this child
        show_all_children( $child->ID, $current_level+1 );

            echo '</li>';

        }

    echo '</ul>';

    }
    
    show_all_children( $post->ID, 1 );