using "session" method from a class other than a controller?

I'm relatively new to Rails, and am wondering if it's possible to use
the "session" method from a class that does not extend
"ActionController::Base"? Can I just do a "require
'action_controller/???'" in order to use it? I would like to store
some session information from a UserService class being called via the
weborb plugin. Thanks in advance...

Martin