19         $sString = 
"ox{$sString}id";
 
   21         $sKey = $this->
_formKey($sKey, $sString);
 
   23         $sString = $sString ^ $sKey;
 
   24         $sString = base64_encode($sString);
 
   25         $sString = str_replace(
"=", 
"!", $sString);
 
   41         $iKeyLength = (strlen($sString) / strlen($sKey)) + 5;
 
   43         return str_repeat($sKey, $iKeyLength);