Updating Group Memberships Throws Error

2014-02-13 23:02:22 Error: [InvalidArgumentException] No CO Specified
Request URL: /registry/co_group_members/updateGroup?%2Fco_group_members%2FupdateGroup=
Stack Trace:
#0 /opt/registry-0.8.4ghr602/app/Controller/CoGroupMembersController.php(137): AppController->beforeFilter()
#1 [internal function]: CoGroupMembersController->beforeFilter(Object(CakeEvent))
#2 /opt/registry-0.8.4ghr602/lib/Cake/Event/CakeEventManager.php(247): call_user_func(Array, Object(CakeEvent))
#3 /opt/registry-0.8.4ghr602/lib/Cake/Controller/Controller.php(674): CakeEventManager->dispatch(Object(CakeEvent))
#4 /opt/registry-0.8.4ghr602/lib/Cake/Routing/Dispatcher.php(182): Controller->startupProcess()
#5 /opt/registry-0.8.4ghr602/lib/Cake/Routing/Dispatcher.php(160): Dispatcher->_invoke(Object(CoGroupMembersController), Object(CakeRequest), Object(CakeResponse))
#6 /opt/registry-0.8.4ghr602/app/webroot/index.php(96): Dispatcher->dispatch(Object(CakeRequest), Object(CakeResponse))
#7