If on a PageType I use the "Simple address for this page", so that I can have two URLs that access the same page. How do I detect in the code behind of a user control on this page which address was used to access the page?

I am looking at implementing a means of turning off pagination for a listing page. I have a page called "Press releases", and added "Press-releases-all" as a Simple address, using this page will turn off the pagination, the idea being to allow users and search engines to view the whole listing without having to have a separate page or query string item on this page.

Thanks