Hrm.. I've gotten the newest mkisofs with the -B flag, and I run:

mkisofs -B boot-141.fs -o NetBSD.iso /home/sean/NetBSD-1.4.1/

and it makes an iso, I burn it, and i get a CD, i insert the cd, attempt
to boot off it, and the Sparcstation tells me: "The file just loaded does
not appear to be executable"...

any ideas on that one?

--Sean