My forums are running ubb.threads 7.5.3p2 and I used to run on a server with:

PHP 4.4.7
MySQL 4.1.22

Now I've just relocated to a new server which is now running:

PHP 5.3.13
MySQL 5.1.62

and I can't page through the topic list when viewing a particular forum index. That is:

http://foo.com/forums/ubbthreads.php/forums/99/1/Title
http://foo.com/forums/ubbthreads.php/forums/99/2/Title
http://foo.com/forums/ubbthreads.php/forums/99/3/Title

and so on, all point to the first page of that forum's index (99/1).

Noting that I'm on an older release (7.5.3), the release notes for 7.5.5 mention some bug fixes for PHP 5.3, so I'm wondering if upgrading will fix my issue, or is there something else at play?