Having worked with windows for warships, making a training environment, I know the following things about it:
a) it does indeed use both Windows XP (for workstations) and Windows Server 2003 (for all the servers)
b) it is such a steaming pile that it makes vanilla Windows Server 2003 look like a work of art
c) if they're offering those patches to you, you don't want them
d) the procedures for installing patches are detailed to the idiot level, but don't actually work when followed
Oh, and the civilians who install it and train the sailors on it did not know that it had the nickname Windows for Warships until I told them; they thought it was a very entertaining name.