O'Donnels Paging Class - Instantiating $page variable

Hi All.
I have just implemented Joe O'Donnels Dynamic paging class....it seems ok apart from one thing..I cannot seem to instantiate the $page variable. My first page of results appear but the link to the others are missing. I have used the $__REQUEST["page"] to try and retrieve it. However i still not sure how its instantiated in the first place

Thanks