The directory of boot.mac exists in OpenBSD/powerpc.
So, Makefile of the directory and so on was used, and I tried to make
ofwboot of NetBSD/powerpc.

I put on <URL:http://www.cec.co.jp/usr/sakamoto/NetBSD/PowerMac/>
<URL:http://www.cec.co.jp/usr/sakamoto/NetBSD/PowerMac/boot.mac/ofwboot.xcf>
is XCOFF format.

I'm afraid I don't have PowerMac though I have BeBox(PowerPC machine) :-)
Don't you try this and send the result to port-powerpc?

Kazuki Sakamoto
sakamoto@cec.co.jp