[eluser]WanWizard[/eluser]
Do we have to guess to what you are doing?
The cart library works perfectly alongside every other use you would have for the session library. I don't know freakauth, and what kind of freaky stuff it does. The cart library uses only one session variable (an array) to store all cart contents, which I don't think is in conflict with any auth library.
So it must have to do with the way you have implemented sessions...