Well, a lets-install-kernel-2.6.31-on-Ubuntu-Jaunty turned out to be a bad idea. The kernel install went OK, but my X went poef. No more bitmap fonts. Looks like some bad interaction between the X Intel driver and the new kernel mode settings.
Anyhow, I figured why not upgrade to Karmic? 15 minutes later my desktop system was completely hosed and I was left staring at a GRUB 1.97 menu.
I never knew that the GRUB command line allows you to type
and only after that you can specify a kernel to boot. After I could login again the system became unstable (it actually crashed with the 2.6.31 kernel).
Ergo: I did a clean install with Karmic Alpha 4 which is running OK right now. And I must say: it feels faster. :-)
Moral of the story: I’m going to stop using Ubuntu mainline kernels and just stick to their stock kernels.
I also hope I can stop myself from upgrading the rest of my systems :-)