protected function GetCurrentUser()
	{
		if (!$this->_cu)
		{
			require_once("verysimple/Authentication/Authenticator.php");
			
			$this->Phreezer->Observe("Loading CurrentUser from Session");
			$this->_cu = Authenticator::GetCurrentUser($this->GUID);

			if ($this->_cu )
			{
				if (get_class($this->_cu) == "__PHP_Incomplete_Class")
				{
					// this happens if the class used for authentication was not included before the session was started
					$tmp = print_r($this->_cu,1);
					$parts1 = explode("__PHP_Incomplete_Class_Name] => ",$tmp);
					$parts2 = explode("[",$parts1[1]);
					$name = trim($parts2[0]);

					Authenticator::ClearAuthentication($this->GUID);
					throw new Exception("The class definition used for authentication '$name' must be defined (included) before the session is started, for example in _app_config.php.");
				}
				else
				{
					// refresh the current user if the object supports it
					if (method_exists($this->_cu, 'Refresh')) $this->_cu->Refresh($this->Phreezer);
				}
			}
		}
		else
		{
			$this->Phreezer->Observe("Using previously loaded CurrentUser");
		}

		return $this->_cu;
	}