function custom_teasers() {
    $teaser_count = 1;

    $recent = new WP_Query('cat=5,4,6&showposts=6');
    while($recent->have_posts()) : $recent->the_post();

        if (($teaser_count % 2) == 1) {
                $top = ($post_count == 1) ? ' top' : '';
                $open_box = "\t\t\t<div class=\"teasers_box$top\">\n\n";
                $close_box = '';
                $right = false;
        }
        else {
                $open_box = '';
                $close_box = "\t\t\t</div>\n\n";
                $right = true;
        }

        if ($open_box != '') {
                echo $open_box;
                thesis_hook_before_teasers_box($post_count);
        }

        thesis_teaser('teaser', false, $right);

        if ($close_box != '') {
                echo $close_box;
                thesis_hook_after_teasers_box($post_count);
        }

        $teaser_count++;

    endwhile;
    wp_reset_query();
}
add_action('thesis_hook_before_content','custom_teasers');