Passing a session to another domain



I am trying to set up a shopping cart checkout system, and in order to do so I need to access my site securely. The site is located at , but the host requires that the secure version be accessed through . Both of these URLs point to the same exact website, but because the domain is different, I cannot carry a session from the normal to the secure side of the website. Since the session contains the information needed to access the items in the user's cart, its rather pointless to enter the checkout page without the session.

I've tried manually setting a session cookie for the new domain (for obvious reasons you cannot set a cookie for "another website," so this route is blocked), and manually passing the contents of the $_GET['PHPSESSID'] variable to session_id() (this sets the session ID correctly, but somehow the information does not follow the ID).

Does anyone have an idea on how to fix this?
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