So starting from where another fellow left off here:

viewtopic.php?f=15&t=11366

viewtopic.php?f=3&t=9967&start=0

https://discussions.apple.com/message/1542636?messageID=1542636#1542636?messageID=1542636

http://ameblo.jp/jozenji/theme-10002170412.html

So the plan is to see if I can boot my Powerbook5,8 using Mac OS ROM 10.2.1. Looking at the Apple Hardware Test file called "AHT_Bootinfo" it appears to be a small version of the Mac OS ROM that calls via OpenFirmware the diags file, which is built in Objective-C. Why it appears to look like OS9 I dont know...

Thats all I have for now.