PHP: requests for non-existent files

Hi,

I use Mathopd with PHP.  There's a minor problem: requests for
non-existent files return "200 OK" and execute index.php (as if
index.php had been requested).

I'd prefer "404 Not Found".  Can I fix this in mathopd.conf?

   ...
   Server {
        Port 8888
        Virtual {
                Host www.example.com
                Control {
                        Alias /
                        Location /webpub/example.com
                        PutEnv { PHPRC=/etc/php/example.com }
                        External {
                                /usr/bin/php { php }
                        }
                        IndexNames { index.html index.php  }
                }

Thanks for any thoughts,

- Martin.