Thought I'd toss this out for comment before investing a lot of time in it since others here know Windows networking a lot better than I do and might have suggestions about Windows capability.

Client has just put in DSL through a Netopia/Caman router providing NAT, because all banking and credit stuff is going Internet now. I've networked all their PCs to it using 192.168.200.n private addresses - except one. Problem with that one is it already has TCP/IP set up to access a remote site through a Cisco router and VPN.

Ethernet card is set up with private address 10.w.x.30, mask 255.255.255.0, gateway 10.w.x.1 (the Cisco). It accesses a single private address in Troy, Michigan, 10.y.z.5, which yields an AIX login.

Presumably there's a way to get requests for 10.213.161.5 to route through the Cisco while everything else outside 192.168.200 range goes throught the Netopia.

Incidentally, every other PC, terminal and printer in the place goes through the same Cisco router to Troy, Michigan, but they're wired serial to port servers that route through the Cisco. There was some reason for setting up this one PC for direct network access, though I haven't remembered what it was yet.