AT&T C++ on Ultrix ?

[Doug Mendonca]

I'm having a grand ol' time trying to get AT&T C++ 2.1 working
on Ultrix 3.1. I'd like to hear from someone who can tell me
whether I need to dive into a full port, or can point out what 
needs to be done to get this thing built correctly. As it stands,
cfront dies with a bus error (or something nasty like that).
I used BSD and bsd3 for SYS and OS (what else?), and have DENSE set. 
Makefile and other shell peculiarities have been fixed, so the build
actually completes...but making the demos is proving to be futile.

Guidance in this matter would be received most enthusiastically.

-doug