I'm have the same problem with with Rails 2.3.3. It looks like the
method_missing defined by acts_as_authorized_user is not being
called. Maybe some other method_missing is clobbering it and not
calling back up the chain. I will look into more if I have time. In
the meantime, I've replaced my is_manager_of calls with has_role
('manager'). These are still defined, so the mixin is still mixing
some.
Jim