OK, I used VboxBFE with the appropriate commanline switches now and get most of my keys recognized (not the arrow keys fro some reason and also the Enter key (the grey one in the numerical block) doesn't work. But it's usable overall and I'm installing Ubuntu 7.10 right now

))
OK. Now I got Ubuntu 7.10 installed and running pretty well. I installed using the i386 ISO file with
VBoxBFE.exe -m 256 -rawr0 -boot d -hda G:\VDD\vbox\VDI\Ubuntu.vdi -cdrom F:\Download\LinuX\ubuntu-7.10-desktop-i386.iso
Now I created a little program object and can run Ubuntu with
VBoxBFE.exe -m 256 -rawr0 -boot c -hda G:\VDD\vbox\VDI\Ubuntu.vdi
Overall performance is great. It boots in 64sec to the login screen and is fully usable after another 30 seconds. OpenOffice.org Writer (version 2.3) loads a new document in 32 seconds (version 2.0.4 needs 19sec in eCS 1.2R).
Some limitations so far:
1. Whenever I shut ubuntu down, I get a message saying: "Error: VM terminated abnormally!" (but it starts nicely the next time, remembering all the setting changes, so I think it's no big deal)
2. No network, no CD-ROM access (just ISO files)
3. The window switches to 1280x1024 whenever the Ubuntu boots, shuts down or presents the login screen (which is kind of annoying on a Screen that is just that size. Once the system is up, it sticks to the 1024x768 I set it to.
Things I didn't figure out so far
1. How do I enable / access the shared folder?
2. Where are the additions for OS/2 (where do I download them from?) And how do I use it in VboxBFE?
3. How to hug Paul for this port ;o)
BTW, VBox runs on this dual Opteron machine in SMP mode, something that VPC never did (I needed to switch the machine to uni-processor to use it...)
Thanks a lot to all people involved. Looking forward to the next steps!
Andreas