Stranded between lenny and squeeze

[Hendrik Boom <hendrik@topoi.pooq.com>]

I'm in the middle of the upgrade from lenny to squeeze.  I have a 
partially working system.  I've been following the instruction ins the 
release notes, http://www.debian.org/releases/stable/amd64/release-notes/
ch-upgrading.en.html and I've gotten as far as upgrading the kernel and 
udev.

hendrik@april:~$ uname -a
Linux april 2.6.32-5-amd64 #1 SMP Tue Jun 14 09:42:28 UTC 2011 x86_64 GNU/
Linux
hendrik@april:~$ 

Both seemed to go well, and I'm now booting into a squeeze kernel and 
seem to have no problems identifying my partitions correctly and my 
netwerk is coming up properly, evidenced by me being able to post this 
message using Pan.

But I'm stuck.  The next step is to issue

apt-get dist-upgrade

but I can't figure out where to type this in.  I can log in using gdm, 
but terminals found there may expire during the upgrade, leaving 
everything in an inconsistent state.

And I can't use cntl-alt-F1 to get a text console, because all I get is a 
blank black screen.  Is gdm taking over the text consoles and disallowing 
them?  How do I get my text consoles back so I can proceed with the rest 
of the upgrade?

Or is there some devious trick I'm missing?  Will an ssh connection from 
another machine survive the upgrade process, for example?

-- hendrik