I don't have any experience setting up such an arrangement. If I had to try, I'd probably try to set up an SQL database: tables with membership information, including timezone, and the disk to which to forward users from each timezone.
You might try posting this question on the MySQL newbie forum, just to see what kind of response you get.
www.mysql.com, click on Support. Scroll down to Community, and click on forum.
You may have to register in order to post.