Upgrade to edgy: kdm or gdm doesn't start automatically

[marc]

After a bit of effort to complete the upgrade of packages - noted 
elsewhere - I'm nearly there. However, when I boot via grub to:

  Ubuntu, kernel 2.6.17.-11-generic [1]

things proceed as expected, with the splash screen, but then I'm dumped 
into the command line (tty1). There's no error message on screen to 
indicate a problem.

>From there I can login and can run startx or kdm (or gdm). I can't alt-
f7, although I can alt-fn where n=1..8

I've tried 

  sudo dpkg-reconfigure kdm

but that doesn't result in any change, although it says it has  
succeeded. Ditto gdm.

Also, when dumped to tty1, I can 

  ps -e|grep kdm

and see that kdm is *not* running, although this is expected by ref to 
init.d, etc.

Any ideas worth a try would be appreciated. 

-- 
Cheers,
Marc