Registration: Passing Source Page Thru Registration Form
 

When a user completes registration, they are typically greeted with a message that includes a link "Click HERE to return to where you were previously". If vBulletin doesn't actually know where the user came from, that link sends them back to the forum homepage.

If I have an overlay which allows registration on my site without leaving the thread currently being viewed, how do I pass the source page variable through the registration process, so that on the register.php?do=addmember landing page they are given a link back to where they started?