protected static function & getConfigInstance ($appRootRelativePath, $systemConfig = FALSE) {
		$app = self::$app ?: self::$app = & \MvcCore\Application::GetInstance();
		$appRoot = self::$appRoot ?: self::$appRoot = $app->GetRequest()->GetAppRoot();
		$fullPath = $appRoot . '/' . str_replace(
			'%appPath%', $app->GetAppDir(), ltrim($appRootRelativePath, '/')
		);
		if (!file_exists($fullPath)) {
			$result = FALSE;
		} else {
			$systemConfigClass = $app->GetConfigClass();
			$result = $systemConfigClass::CreateInstance();
			if (!$result->Read($fullPath, $systemConfig)) 
				$result = FALSE;
		}
		return $result;
	}