I'm having some problems with Arne's Sitemap Generator 3 beta plugin. When I activate the plugin, the Plugin Management page stops listing any of the plugins I have in my directory. On the Dashboard, the incoming links list from Technorati and the WordPress Development Blog items are replaced with an Internal Server Error message.
The Sitemap Generator seems to work fine. It shows up under the Options page and I am able to manually generate a new sitemap.