Over the weekend a firmware update for Lotus Protector from Mail Security was released. You may have issues installing the fix. There is a technote on the ISS support site here. The technote tells you to  install a hotfix as below:

1.        SSH to your appliance (login as 'root').
2.        Download the hotfix using the command: wget http://upload.cobion.com/download/pnmss/msupdate-hotfix-xpu-1.sh
3.        Make the hotfix executable: chmod +x msupdate-hotfix-xpu-1.sh
4.        Apply the hotfix using the command: ./msupdate-hotfix-xpu-1.sh

BUT even after the hotfix the firmware update still fails.

There is also a thread on Notes.net about this issue here.