PHP Class not found

[Al_katraz984]

class QWConfiguration 
{   
protected static $mClassName = "QWConfiguration"; //By changing this before the configuration is read, an application can force the use of a specified configuration class
public function __construct()   {    //initialize the values   }     
public static function getClassName()   {    return self::$mClassName;   }   public static function setClassName($aClassName)   {    self::$mClassName = $aClassName;   }     
static public function getConfiguration()   
{    
$aClassName = self::getClassName();    
$aClass = new $aClassName();    
return $aClass;   
}  
} ?> 

scusa ero col cell.. poco fa