Facebook IFrame app choking on third party cookies

[eluser]Unknown[/eluser]
I hope someone can help me.
I have a fully functioning CI website that I'm trying to add to facebook as an IFrame application. It works fine unless third party cookies are disallowed. I've searched for workarounds but couldn't find anything that works.
Does anyone know how to adapt an application to work on facebook without duplicating all the controllers to be FB specific?
If not, then how can I append FB session id key to CI url and then strip it off in my controller before handing it off. example:
get page http://mysite.com/index.php/con1/var1/SESID-123434347 -> strip the sesid segment and call index.php/con1/var1 instead.

Any help would be greatly appreciated.