def session(session_store = nil)
session_store ||= default_session_store
if class_name = self.class.registered_session_types[session_store]
session_stores[session_store] ||= Object.full_const_get(class_name).setup(self)
elsif fallback = self.class.registered_session_types.keys.first
Merb.logger.warn "Session store '#{session_store}' not found. Check your configuration in init file."
Merb.logger.warn "Falling back to #{fallback} session store."
session(fallback)
else
msg = "No session store set. Set it in init file like this: c[:session_store] = 'activerecord'"
Merb.logger.error!(msg)
raise NoSessionContainer, msg
end
end