/**
  * gets a supported locale
  *
  * @param   string $_localeString
  * @return  Zend_Locale
  * @throws  Tinebase_Exception_NotFound
  */
 public static function getLocale($_localeString = 'auto')
 {
     Zend_Locale::$compatibilityMode = false;
     if (Tinebase_Core::isLogLevel(Zend_Log::DEBUG)) {
         Tinebase_Core::getLogger()->debug(__METHOD__ . '::' . __LINE__ . " given localeString '{$_localeString}'");
     }
     try {
         $locale = new Zend_Locale($_localeString);
         // check if we suppot the locale
         $supportedLocales = array();
         $availableTranslations = self::getAvailableTranslations();
         foreach ($availableTranslations as $translation) {
             $supportedLocales[] = $translation['locale'];
         }
         if (!in_array($_localeString, $supportedLocales)) {
             if (Tinebase_Core::isLogLevel(Zend_Log::DEBUG)) {
                 Tinebase_Core::getLogger()->debug(__METHOD__ . '::' . __LINE__ . " '{$locale}' is not supported, checking fallback");
             }
             // check if we find suiteable fallback
             $language = $locale->getLanguage();
             switch ($language) {
                 case 'zh':
                     $locale = new Zend_Locale('zh_CN');
                     break;
                 default:
                     if (in_array($language, $supportedLocales)) {
                         $locale = new Zend_Locale($language);
                     } else {
                         if (Tinebase_Core::isLogLevel(Zend_Log::DEBUG)) {
                             Tinebase_Core::getLogger()->debug(__METHOD__ . '::' . __LINE__ . " no suiteable lang fallback found within this locales: " . print_r($supportedLocales, true));
                         }
                         throw new Tinebase_Exception_NotFound('No suiteable lang fallback found.');
                     }
                     break;
             }
         }
     } catch (Exception $e) {
         if (Tinebase_Core::isLogLevel(Zend_Log::NOTICE)) {
             Tinebase_Core::getLogger()->notice(__METHOD__ . '::' . __LINE__ . ' ' . $e->getMessage() . ', falling back to locale en.');
         }
         if (Tinebase_Core::isLogLevel(Zend_Log::TRACE)) {
             Tinebase_Core::getLogger()->trace(__METHOD__ . '::' . __LINE__ . ' ' . $e->getTraceAsString());
         }
         $locale = new Zend_Locale('en');
     }
     if (Tinebase_Core::isLogLevel(Zend_Log::DEBUG)) {
         Tinebase_Core::getLogger()->debug(__METHOD__ . '::' . __LINE__ . " selected locale: '{$locale}'");
     }
     return $locale;
 }