Ok, I build myself a pair of rsa keys and now it works.

Btw. thank you very much for net-ssh!! It really rocks!! 



>
> Woops. My bad. Apparently you can't use public/private key
> authentication using a dsa key right now. I'll work on that. I just need
> to not use the 'sign' method of the key object, since that doesn't work
> for all key types...
>
> Look for a fix in 0.0.4... In the meantime, keys generated using
> 'ssh-keygen -t rsa' should work fine. (If they don't, let me know,
> because they work for me.)