>My question is (I guess) where is the equivalent termcaps file
>on the 3000 (/usr/lib/terminfo ?) and how safe is it to just
>move the termcaps from the Sun?

The equivalent location is /usr/lib/terminfo on MPE! To be honest, I'd
move it and find out!

BTW - I use xterm quite a bit and have moved over an xterm termcaps file
such that I get correct behavior under the shell and I've had no problem
with that (other than some escape sequences that the shell issues before
my TERM environment variable gets set, and that could be resolved by
hacking /etc/profile).