Saving session across domains
 

I'm looking for a way to save a vbulletin session across domains.
The issue I have is my first domain, site1.com runs everything on the forum.
I want to include another domain site2.com that handles custom forum pages (like a shop plugin, arcade, etc) which are all just plugins to vbulletin.
the real URL to the shop plugin is something like site1.com/shop (and everything else following it for further pages)
but I want site2.com to basically be site1.com/shop

If it makes any difference, the registration/login will still be site1.com on the shop/arcade section, it's just if you'd like to participate in site2.com, you'd need to login at site1.com. If that makes any sense..

You might try experimenting with putting the sessionid on the urls (which is done automatically if a user has cookies disabled). There's a function $vbulletin->session->set_session_visibility($invisible) which is called in init.php to show or hide the sessionid depending on a few conditions.

I haven't tried this and I'm not sure why sessionids are normally hidden, except that it makes the urls more readable, so maybe there's an issue with doing this that I don't understand.

Person A posts a link that includes his session ID
Person B follows that link while Person A's session is still active
Person B takes over Person A's session.

I used to work for an ecommerce company whose shopping cart/session ID was passed by a URL parameter. When a link went viral, it was not pretty.