power failure during upgrade

[Joe Mc Cool <joe@benburb.demon.co.uk>]

in order to upgrade from woody to sarge I did:

   apt-get update
   apt-get dist-upgrade

off it went, but unfortunately I had a power failure during the upgrade 
and my system got hosed.  (I repeated the above steps, but my system 
would then boot only with a ro root filesystem.)

So, coward that I am, I restored my entire system from a woody tape.

Now when I repeat the above two steps I am told there are zero packages 
to upgrade :-(

Thanks

Joe