You have to find the stack for NT 3.1, as Microsoft replaced the BSD stack as of 4.0.
OK--btw, do you still have copies of the NT 3.1 boot disks--I have an ISO of a CD I picked up for cheap, but can't run it in VMware or qemu without the blasted boot disks. And my Win98-based general one doesn't work.
i can then check NT 3.1 and see what it says. I didn't see it in NT 3.51, btw.