> I have a Mac 400MHZ G4 Gray tower.
> I succefully entered Open Firmware and installed NetBSD 1.6.2 from CD. 
> When the installation was complete, I got a massage that the install 
> is complete and the system will now be able to boot to NetBSD. But 
> after rebooting the system, the flashing question mark apears and 
> nothing elese happens.

hi,

a Mac doesn't boot NetBSD 'out-of-the-box' as it does boot Mac OS 9 or 
Mac OS X.

please read the installation and boot instructions at

http://netbsd.org/Ports/macppc/SystemDisk-tutorial/

and

http://netbsd.org/Ports/macppc/faq.html

that should solve your problem. you certainly will have to fiddle 
around a bit with OpenFirmware, so please read (and understand!) what 
you are doing, because it's not always harmless...

regards,

timo