Spawned node incomplete?

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I was able to use the following the code in ROS fuerte to spawn the JointTrajectoryAction node:

<node name="arm_controller_spawner" pkg="pr2_controller_manager" type="spawner" args="arm_controller" />
<group ns="arm_controller">
<node name="arm_joint_trajectory_action_node" pkg="joint_trajectory_action" type="joint_trajectory_action" />
</group>

The correctly spawned node contains the following topics:

/arm_controller/command
/arm_controller/follow_joint_trajectory/cancel
/arm_controller/follow_joint_trajectory/feedback
/arm_controller/follow_joint_trajectory/goal
/arm_controller/follow_joint_trajectory/result
/arm_controller/follow_joint_trajectory/status
/arm_controller/joint_trajectory_action/cancel
/arm_controller/joint_trajectory_action/feedback
/arm_controller/joint_trajectory_action/goal
/arm_controller/joint_trajectory_action/result
/arm_controller/joint_trajectory_action/status
/arm_controller/state

However, when I do the same thing in ROS indigo, I only got two topics:

/arm_controller/command
/arm_controller/state

It seems that the JointTrajectoryAction is not started successfully? If you have any idea it will be greatly appreciated!

Some more observations:

When I tried to kill Gazebo (ctrl+c) , I got the following "traceback" info:

Traceback (most recent call last):
  File "/home/david/catkin_ws/src/pr2_simulator/pr2_mechanism/pr2_controller_manager/scripts/spawner", line 161, in <module>
    if __name__ == '__main__': main()
  File "/home/david/catkin_ws/src/pr2_simulator/pr2_mechanism/pr2_controller_manager/scripts/spawner", line 92, in main
    rospy.wait_for_service('pr2_controller_manager/load_controller')
  File "/opt/ros/indigo/lib/python2.7/dist-packages/rospy/impl/tcpros_service.py", line 159, in wait_for_service
    raise ROSInterruptException("rospy shutdown")

If I do a "rosservice -list" command, I find 'controller_manager/load_controller' instead of 'pr2_controller_manager/load_controller'