Warning for null parameters

Warning/error found while trying to reproduce other issues in Cou.php; is a simple fix

2012-02-10 16:33:10 Warning: Warning (2): array_search() expects parameter 2 to be array, null given in [/Applications/MAMP/htdocs/gears/trunk/app/Model/Cou.php, line 191]
Trace:
array_search - [internal], line ??
Cou::isChildCou() - APP/Model/Cou.php, line 191
CousController::checkWriteDependencies() - APP/Controller/CousController.php, line 167
StandardController::edit() - APP/Controller/StandardController.php, line 350
ReflectionMethod::invokeArgs() - [internal], line ??
Controller::invokeAction() - CORE/Cake/Controller/Controller.php, line 473
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 104
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96

2012-02-10 16:33:53 Error: [BadRequestException] The request has been black-holed
#0 /Applications/MAMP/htdocs/gears/trunk/lib/Cake/Controller/Component/SecurityComponent.php(214): SecurityComponent->blackHole(Object(CousController), 'csrf')
#1 [internal function]: SecurityComponent->startup(Object(CousController))
#2 /Applications/MAMP/htdocs/gears/trunk/lib/Cake/Utility/ObjectCollection.php(104): call_user_func_array(Array, Array)
#3 /Applications/MAMP/htdocs/gears/trunk/lib/Cake/Controller/Controller.php(606): ObjectCollection->trigger('startup', Array)
#4 /Applications/MAMP/htdocs/gears/trunk/lib/Cake/Routing/Dispatcher.php(101): Controller->startupProcess()
#5 /Applications/MAMP/htdocs/gears/trunk/lib/Cake/Routing/Dispatcher.php(86): Dispatcher->_invoke(Object(CousController), Object(CakeRequest), Object(CakeResponse))
#6 /Applications/MAMP/htdocs/gears/trunk/app/webroot/index.php(96): Dispatcher->dispatch(Object(CakeRequest), Object(CakeResponse))
#7