Yeah!

I got it booted (and NetBSD installed), many thanks to Michael Wolfson for
the final hint: I burned a CD from boot.fs - that's all. While this is not
a valid ISO 9660 CD, my OF 2.0.4 can boot from it just fine, using

  boot ata/atapi-disk:0,ofwboot.xcf -a

first and then answering

  netbsd

to the boot prompt (without the -a it won't work, don't know nor care why).


Martin