They are the rules:

RewriteRule ^$ index.html [QSA]
RewriteRule ^([^.]+)$ $1.html [QSA]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.*)$ dispatch.cgi [QSA,L]
#RewriteRule ^(.*)$ dispatch.fcgi [QSA,L]

 They are the errors I can see in /var/log/apache2/error.log

[Sat Jun 23 17:42:56 2007] [alert] [client 127.0.0.2] /var/www/todo/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration
[Sat Jun 23 17:43:12 2007] [alert] [client 127.0.0.2] /var/www/todo/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration
[Sat Jun 23 17:43:12 2007] [alert] [client 127.0.0.2] /var/www/todo/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration
[Sat Jun 23 17:43:25 2007] [alert] [client 127.0.0.2] /var/www/todo/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration