Pass vars in URL

Hello, My host has upgraded to 4.2 but still uses the old ini setting. I am trying to rewrite my scripts so when the day comes for my host to make the change I will be ready. Everything has been going well till now. I have been passing an id through a url string. Now when I try to pass the id it show up in the url but does nothing. If i check if it is set, it is not. IT is supposed to pass the id number to mysql on the linked page. I there something I am missing some new way or do I need to turn on something in the ini? TIA gary