Get posts published between two dates

<?php
  function filter_where($where = '') {
        $where .= " AND post_date >= '2009-03-17' AND post_date <= '2009-05-03'";
    return $where;
  }
add_filter('posts_where', 'filter_where');
query_posts($query_string);
while (have_posts()) :
      the_post();
      the_content();
endwhile;
?>