track vars problem

Hi, I installed PHP 4 on Redhat 6.2. the setting for track_vars is "on", though, I cannot use the name of the variable when I refer to a "URL" variable. I manage to get to it's value only by using the $HTTP_GET_VARS I know that the track_vars setting is the answer, but as I mentioned before, it is set on "on". By the way, is there any connection to anything the php.ini file contains? Or is it the compilation only that sets these things. (in the php.ini it is set on "on" too) Thanks, David Treves.