I think I found the problem. It isn't too compatible with register_globals = off (the $PHP_SELF var assumes it has already been extract($_SERVER) or assumes register_globals=on)

[edit]
maybe not. looking further down categories.php shows you are using $_SERVER['PHP_SELF'] then storing it to $PHP_SELF
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[edit2]
great. it seems to show the proper links on my localhost but not online. grrr
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