XML Sitemap is designed to be extended by external modules. If you need capabilities which are not provided by existing modules, you can add them to your own module. You can view the API documentation for XML sitemap at http://api.lullabot.com/about.
If your module's only purpose is to extend XML sitemap, you should observe the following coding standards:
- Your module's .info file should look something like this:
name = XML sitemap mymodule
description = "A short description for my module."
core = 6.x
package = XML sitemap
dependencies = xmlsitemap
- Be sure to follow Drupal's coding standards as well.