web statistics for virtual domains on server: not defined/config file not found?

Warning: dir(VHOSTDIR not defined/config file not found?): failed to open dir: No such file or directory in /mnt/fmirror4/gmirror/ports/www/webstats/work/webstats_0.3/scripts/php/webstats.php on line 35

Fatal error: Call to a member function on a non-object in /mnt/fmirror4/gmirror/ports/www/webstats/work/webstats_0.3/scripts/php/webstats.php on line 36