Update apt from the Distribution Manager and afterwards:
apt-get install ssh
I still couldn't get MySQL server 5.1 up and running; I have a strange feeling there's something wrong with the distribution, as I've just installed it on my ubuntu box without any errors.
Can you give it a try?
apt-get install mysql-server-5.1
It should print out something about package not configured yet at some point.
EDIT: Forgot to add
apt-get install openssh-server
Start the ssh server with
with "sshd" only you'll get the following error:
sshd re-exec requires execution with absolute path
Afaik, the sshd $PATH is defined wrong for the service so that's why running it simply with sshd won't work.
Test the functionality afterwards with:
Forgot to add the info you requested for sources.list:
deb http://ftp.debian.org/debian squeeze main non-free
deb-src http://ftp.debian.org/debian squeeze main non-free
deb http://ftp.debian.org/debian squeeze/squeeze main non-free
deb-src http://ftp.debian.org/debian squeeze/squeeze main non-free
Should be the same though I think. What's yours?