public function injectIdentityModel(MvcEvent $event)
	{
	    $viewModel = $event->getViewModel();
	    if ($viewModel->getTemplate() == 'layout/layout') {
	        $servies = $event->getApplication()->getServiceManager();
	        $appConfig = $servies->get('config');
	        if (isset($appConfig['view_model_identity'])) {
	            $config = $appConfig['view_model_identity'];
	        } else {
	            throw new \Exception('view_model_identity key not found in configuration');
	        }
	        if (!$servies->has($config['authenticationService'])) {
	            throw new \Exception('Auththentication service not found');
	        }
	        if (!$servies->has($config['identity'])) {
	            throw new \Exception('Identity not found');
	        }
	        $childViewModel = new IdentityViewModel(array(
	            'auth'     => $servies->get($config['authenticationService']),
	            'identity' => $servies->get($config['identity']),
	        ));
	        if (isset($config['template'])) {
	            $childViewModel->setTemplate($config['template']);
	        }
	        if (isset($config['captureTo'])) {
	            $childViewModel->setCaptureTo($config['captureTo']);
	        }
	        $viewModel->addChild($childViewModel);
	    }
	}