web_service_dispatching_mode :layered

Hello All, I am using layered dispatching with AWS. My controller looks like this:

  web_service_dispatching_mode :layered   web_service_scaffold :invoke

  web_service :user, UserService.new

Here is the part of UserService that is failing (It's saying session isn't an object):

class UserService < ApplicationController   web_service_api UserApi

  def login(username, password)     logged_in_user = User.login(username,password)     if logged_in_user       session[:user_id] = logged_in_user.id       return true     else       return false     end   end end

Can you use sessions with layered dispatching? If so, how? Do I need to require a library manually? Using sessions worked with direct dispatching (which I believe is SOAP, rather than XML-RPC). Thanks in advance!