add_allowed_type (OpenID::AssociationNegotiator)

    # File lib/openid/association.rb, line 219
        def add_allowed_type(assoc_type, session_type=nil)
          if session_type.nil?
            session_types = self.class.get_session_types(assoc_type)
          else
            self.class.check_session_type(assoc_type, session_type)
            session_types = [session_type]
          end
          for session_type in session_types do
            @allowed_types << [assoc_type, session_type]
          end
        end