Tomi, P375, Fourth paragraph, of Blueprints says that a local architecture (which PetStore is) does not need BusinessDelegates and ServiceLocators. The WebController passes an Event to the EJBController. The EJBController has a command pattern which passes the event to the correct Session Facade (note. Doesn't have to be a Session Facade. Could be a POJO).
The EJBController is stateful because it is storing conversational state on behalf of a client (i.e. shopping cart).
Choosing between WAF Controllers or J2EE patterns as components is a tough one. Hopefully, someone who's passed can answer better. I suppose you can do either as long as the comments explain things. Do you model based on Cade or Petstore?