RewriteEngine On
RewriteRule ^(sitemap.*\.(xml|txt)(\.gz)?)$ vbseo_sitemap/vbseo_getsitemap.php?sitemap=$1 [L]

Options +FollowSymLinks
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ http://www.quebecunderground.net/camarade.php?username=$1 [R]