Better yet, you should seriously consider finding a way to do this using POJO techniques without all the convoluted
JSF stuff.
The only time I ever do anything like this is when I need a true top-level session object and it can't be a managed bean.
And then I offload the actual manual session object get/put to a utility class so that my core core isn't littered with a lot of explicit javax.faces constructs. That way my code is easier to unit-test offline and I won't get clobbered the next time a new set of framework functions comes out.