Sorry for the slow reply. I checked it out. You are running 6.4.0.1, and I wrote this on a 6.5 board, so there might be some differences, but it should work.
Also, you really should get your host to upgrade your PHP as you are running 4.0.6. The exact problem is the way I get the query string (?forum=46) must not be recognized on the older version of PHP. Either way, I would recommend upgrading the PHP as there are some vulnerabilities fixed.
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