Open Stack

Hi,
The change is cool and understood. My concern here is that if someone 
has deployed Folsom, when they upgrade to Grizzly then the code will be 
broken. In the original configuration the the entry was:
notification_driver =quantum.openstack.common.notifier.rabbit_notifier
This has now been changed to:
notification_driver =quantum.openstack.common.notifier.rpc_notifier
Is this something that needs to be taken care of internally by Quantum 
or something across OpenStack?
Thanks
Gary