Sitemap xml in Webby

---
extension: xml
layout:    nil
dirty:     true
filter:    erb
---
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
<% @pages.find(:all ).each do |page| -%>
  <url>
    <loc><%= server_url_for(page)%></loc>
    <lastmod><%= page.mtime.strftime("%Y-%m-%dT%H:%M:%S+00:00") %></lastmod>
    <changefreq>monthly</changefreq>
    <priority><%= 1.0 - (page.url.split('/').length / 10.0) %></priority>
  </url>
<% end -%>
</urlset>