Don.  It's worth noting that if you're careful with your port to FreeBSD, 
the code "should just work" under NetBSD.  Also, you could try bringing up
NetBSD on an I386 box to do your port as well.  The programming
environments under FreeBSD and NetBSD are really very similar, and if you
keep the idea of running the code under both in mind when you do the port,
I think you'll find you can produce a very portable port.
-Brian