(This will be very helpfull, when I can start the System Disk utility again.
At this moment my OSX System is freezing after succesfull login. And I have no bootable CD)

It looks that nvram -p shows the same information like printenv
after booting in OpenFirmware (command + option + o + f) does.

Somebody tried
"setenv boot-device ultra0:\\tbxi"
on the OpenFirmware prompt to boot OS9

but this does not work for me.

It looks like the syntax has changed because my boot-device
is set to "hd:,\\:tbxi"

What is the right setting to boot OS9? (on an iBook)

Try running the OS X disk utility, and if that doesn't find anything, try booting into 9 from a CD and running the disk utility there -- or better yet, norton (the new version that doesn't muck up OS X stuff!) or techtool.

Basically, OS X seems to foccasionally ark up some of the drive's data about itself (beta problem, definitely) and this makes the system disk control pane (in OS X) crash. By fixing the problem, you can get system disk to work again.

HTH,
Zach

For OS9 on my Powerbook it's:

setenv boot-device /AAPL,ROM
setenv boot-command boot

but this different on other machines. Open the System Disk Control Panel (the OS9 one) and Option-Double-Click a device to see it's commands.