Yes it does use a hardware firewall.
Now I've got it back here, I'm using it on a connection that is shared out thru my own PC (using XP Home), via a crossover ethernet cable, and it works perfectly.
I've installed messenger, which the owner could not even download, I set up a temporary Bebo a/c, which they could not even access the Bebo homepage, and all other websites they were having problems with work perfectly !!!
Surely the router can't be that incompatible with Vista 64 ?? I always regarded routers as pretty much a pass through device that filters traffic without really being interfered with by the OS ?
Maybe I should suggest a different model ?