404 Error with Sitemaps and SEO Plugin

I installed the Sitemaps and SEO plugin according to the instructions on the install file on two of our MU installs (one 7.1, one 7.0).

The plugin on the WPMU 7.0 blog seems to work fine. On the 7.1 install however we receive 404 errors when trying to visit http://blogproautomotive.com/sitemap.xml

I checked and double checked that the files were dropped in the correct folders and the .htaccess file was updated. Thoughts? Let me know if you need more info.