Works fine now, looks like a problem in the userland.
(What went previously wrong: rcS.d/S40networking kept hanging and so
did the booting process. Now I could have a look at the process table,
it appeared that bind9 was somehow giving trouble when the dhclient
tried to set /etc/resolv.conf.
I did not look into detail what went wrong or why at all bind9
influences scripts called from rcS.d (?). I just removed the bind9
package and the O2 is booting fine now. I might have a look at this
later, as it was not a problem before.. )
By the way, before it ran Thiemo's 2.6.12 kernel from