Opera/9.80 (S60; SymbOS; Opera Mobi/SYB-1204232256; U; de) Presto/2.10.254 Version/12.00

   var $deviceSymbian = 'symbian';
+   var $deviceSymbOS = 'symbos';
   var $deviceS60 = 'series60';
   var $deviceS70 = 'series70';
   var $deviceS80 = 'series80';
   var $deviceS90 = 'series90';

...

   function DetectSymbianOS()
   {
       if (stripos($this->useragent, $this->deviceSymbian) > -1 || 
+           stripos($this->useragent, $this->deviceSymbOS) > -1 ||
           stripos($this->useragent, $this->deviceS60) > -1 ||
           stripos($this->useragent, $this->deviceS70) > -1 || 
           stripos($this->useragent, $this->deviceS80) > -1 ||
           stripos($this->useragent, $this->deviceS90) > -1)
         return $this->true; 
      else
         return $this->false; 
   }