I have a shopping system (written in php, using jQuery ajax) in which I keep cart details in a session multidimensional array. Everything works fine on Chrome and Firefox. It also works fine on IE9 (and in compatibility) mode when running on localhost (I'm using WAMP). However, as soon as I copy everything to the remote server (shared hosting) something goes wrong and weird. Sessions don't work correctly on IE.
For example, when I add product to cart (multidimensional session array) it won't update the session (even tho I can see ajax passing all values to the script that sets up session vars correctly). Or, it will update the session, but I would only be able to see it after changing site address from www.site.com to site.com (or other way around).
This works fine on the same IE when running locally on my computer (through WAMP)
Let me know if you want to see parts of the code. Perhaps there's some obvious bug or rule that you can spot just by reading the description