Generates a sitemap.xml from Wordpress

wp-sitemap.php

<?php
include( './wp-load.php' );
header("Content-Type: application/xml");
?>
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"> <?php
foreach(get_pages() as $page) { ?>
  <url>
    <loc><?php echo get_page_link( $page->ID ); ?></loc>
    <lastmod><?php echo date("Y-m-d", strtotime($page->post_modified)); ?></lastmod>
  </url>
<?php } ?>
</urlset>