function setOption($name, $value) 
    {
        $availableOptions = array('errorHandlingAPIBreak', 'hashedDirectoryUmask', 'hashedDirectoryLevel', 'automaticCleaningFactor', 'automaticSerialization', 'fileNameProtection', 'memoryCaching', 'onlyMemoryCaching', 'memoryCachingLimit', 'cacheDir', 'caching', 'lifeTime', 'fileLocking', 'writeControl', 'readControl', 'readControlType', 'pearErrorMode', 'hashedDirectoryGroup', 'cacheFileMode', 'cacheFileGroup');
        if (in_array($name, $availableOptions)) {
            $property = '_'.$name;
            $this->$property = $value;
        }
    }