Horde_Imsp_Client_Base::quoteSpacedString PHP Method

    public static function quoteSpacedString($string)
    {
        if (strpos($string, ' ') !== false || preg_match(self::MUST_QUOTE, $string)) {
            return '"' . $string . '"';
        } else {
            return $string;
        }
    }

 /**
  * Unlocks a previously locked address book.
  *
  * @param string $abook     Name of address book containing locked entry.
  * @param string $bookEntry Name of entry to unlock.
  *
  * @throws Horde_Imsp_Exception
  */
 public function unlockEntry($abook, $bookEntry)
 {
     // Start sending command.
     $this->_imsp->send('UNLOCK ADDRESSBOOK ', true, false);
     // {} for book name?
     if (preg_match(Horde_Imsp_Client_Base::MUST_USE_LITERAL, $abook)) {
         $biBook = sprintf("{%d}", strlen($abook));
         $this->_imsp->send($biBook, false, true, true);
     }
     $this->_imsp->send("{$abook} ", false, false);
     //How bout for entry name?
     if (preg_match(Horde_Imsp_Client_Base::MUST_USE_LITERAL, $bookEntry)) {
         $biEntry = sprintf("{%d}", strlen($bookEntry));
         $this->_imsp->send($biEntry, false, true, true);
         $this->_imsp->send($bookEntry, false, true);
     } else {
         $bookEntry = $this->_imsp->quoteSpacedString($bookEntry);
         $this->_imsp->send("{$bookEntry}", false, true);
     }
     $response = $this->_imsp->receive();
     switch ($response) {
         case 'NO':
             // Could not create abook.
             $this->_imsp->_logger->err('IMSP server is unable to perform your request.');
             throw new Horde_Imsp_Exception('IMSP server is unable to perform your request.');
         case 'BAD':
             $this->_imsp->_logger->err('The IMSP server did not understand your request.');
             throw new Horde_Imsp_Exception('The IMSP server did not understand your request.');
         case 'OK':
             $this->_imsp->_logger->debug("UNLOCK ADDRESSBOOK on {$abook} {$bookEntry} OK");
     }
 }