public function readString()
    {
        $stringReference = $this->readInteger();

        //Check if this is a reference string
        if (($stringReference & 0x01) == 0) {
            // reference string
            $stringReference = $stringReference >> 1;
            if ($stringReference >= count($this->_referenceStrings)) {
                require_once 'Zend/Amf/Exception.php';
                throw new Zend_Amf_Exception('Undefined string reference: ' . $stringReference);
            }
            // reference string found
            return $this->_referenceStrings[$stringReference];
        }

        $length = $stringReference >> 1;
        if ($length) {
            $string = $this->_stream->readBytes($length);
            $this->_referenceStrings[] = $string;
        } else {
            $string = "";
        }
        return $string;
    }