How to set session variable in plug-ins

Rails
1

I’m working on a plug-in which has to manipulate some session varibles
Unfortunately I end up with “Symbol as array index” errors.

Probably the error occurs in a point that I never think about but here’s
an abstract plug-in which generates the same error.

It fails in the line of assignment “session[:aaa_uid] = uid” with
“Symbol as array index” error.

module Legacy
module Rails #:nodoc:
module Test #:nodoc:

def self.included(base)
  base.extend(ClassMethods)
end

  module ClassMethods
    def uses_test_plug(options = {})
      class_eval do
        extend ::Legacy::Rails::Test::InstanceMethods
      end

      before_filter do |controller|
        set_aaa_uid("jdoe")
      end
    end
  end

  module InstanceMethods
    def set_aaa_uid(uid)
      session[:aaa_uid] = uid
    end
  end

  module SingletonMethods
  end

end

end
end

ActionController::Base.class_eval do
include ::Legacy::Rails::Test
end