Hold your horses, I'm just a simple user without too much
understanding of the hardware trying to get most out of his PowerBook
G3 Lombard (with broken L2 cache: 33bogomips) which I got a week ago :)

What makes you think it has a broken L2 cache ? The 33 bogomips are
totally unrelated, it's the timebase frequency. Bogomips are NOT a
benchmark and on the powerpc architecture, and not even related to the
processor speed at all (but to the frequency of the timebase input).

It seems suspend-to-ram is working to some extend, or at least
'should' work out-of-the-box. When I close the lid and reopen it, it
resumes 'a little': PCMCIA cards seem to power up again (TX/RX WiFi
led starts to flash again), but the screen stays dark. I haven't tried
to debug this yet, since getting WiFi to work

Does it work better without the PCMCIA card ? Is it properly going to
sleep (snoozing LED) ? Also make sure you are using the proper video
driver (atyfb on the lombard) and not booting with "novideo" or
"video=ofonly".

Furthermore I'm not interested in kexec if 'all is working'. But since
'rebooting' already hangs after the powerdown, I'm more focused on
getting the normal 'reboot' working.

That is the strange thing... does it reboot fine in MacOS ?

Since you're using more esotoric hardware, I'm afraid it will be quite
difficult without getting your hands very dirty.

Ben.