:: 2.6.33 boots, but
O.K., so after having updated dash, I managed to install 2.6.33 kernel, it booted fine till kubuntu boot splash screen and... then nothing. Black screen. I tried booting on "recovery mode" with same results. I tried adding "1" at the line of kernel option in /boot/grub/menu.lst, I also changed the services to be launched at the default runlevel (in Ubuntu, especially in older releases, runlevels are different from the rest of Unix world) etc etc, but to no avail. What was going on?
Well, I found this"Screen(s) found, but none have a usable configuration" in my Xorg.0.log, which means somehow X was launched. So, not knowing anything else to do, I decided to blacklist the newly compiled graphic driver "nouveau" by adding a line with blacklist nouveau in /etc/modprobe.d/blacklist. Then I could boot in recovery mode, fix Xorg.conf and boot again in normal mode. At last, I have a new operational kernel. Well, as you may expect this is not yet end of the story...