hello fans of seam!

is it possible to implement a sort of abstract factory concept with some seam components?
i can not get it to work...

this is my scenario:

public interface myService {
   public void checkAccess(someObjects);
}

public abstract class myServiceImpl implements myService {
   public void checkAccess(someObjects) {
   ...
   }
}

public class myServiceImplAdmin extends myServiceImpl {
   public void checkAccess(someObjects) {
   ... access check for admin users ...
   }
}

public class myServiceImplUser extends myServiceImpl {
   public void checkAccess(someObjects) {
   ... access check for customers ...
   }
}

upon login id like to check if the user is admin or a normal user. if the user is a admin the myServiceImplAdmin should be used, else the myServiceImplUser...

i can do this with the @factory method and it works! but it works only for pojos, which means i can not access some seam components (for example Identity, Entitymanager) from the the @Factory method returned objects. (myServiceImplAdmin/myServiceImplUser)

any hints, ideas how i can achieve this?

thanks for helping