I use the redirectors for my old threads 6.5 board to bring the old bookmark user to the new board. I reviev the php error log on my server (php5.2.0) and found:
PHP Notice: Undefined index: Number in /var/.../ubbthreads/showflat.php on line 64
PHP Notice: Undefined variable: PATH_INFO in /var/.../ubbthreads/showflat.php on line 68