rvp I don't know who came up with "yellow pee". I've never heard that, and it wouldn't make sense like "yellow pages" does, which is the only explanation I've ever heard. In the olden days here, if you wanted to look up a phone number or address, you'd look in the Yellow Pages. (White Pages for residential, but there were iconic TV ads for the Yellow Pages, so that's why it's significant.)
Well anyway, the PAM system change did the trick. I never took the time to understand PAM, so I would've never found that without your help. Thank you!
Also; what NIS sends for passwords looks exactly like master.passwd
In the past, the passwords would be decoded and sent as plaintext, that was a cheap way to find out everyone's password.
Now, I'm guessing PAM is behind the fact that I cannot telnet to this server from a NetBSD machine, since upgrading to 10.0.