upgrade halted

[Jasper Bal]

After nummerous advices on the list that I should upgrade, I decided to 
try remote upgrading.

At the folowing step:
Reboot on the new kernel: This might be a tempting step to skip, but it 
should be done now, as usually, the new kernel will run old userland 
apps (such as the soon to be important reboot!), but often a new 
userland will NOT work on the old kernel.

something went wrong. I issued a reboot. And when the system came back 
up, SSH didn't recognize any of my passwords. All the services seem to 
be running though. I even have unchrooted access through FTP. I'm in 
wheel group but have no access as root with FTP. Already checked 
ftpusers, but root is hashed (yes, I know this is wrong). Either I 
forgot the password, or something has changed.

Any hints? Did I do something wrong? Is there a fix? Or do I have to 
travel 400 km?

Regards,
Jasper