Hello,

Thanks to everyone who posted a suggestion.
This is what I did, I ssh'ed in as root and gave `user' a password. Then I cleared the known_hosts files in both the N900 and the ubuntu machine. I also chmod'ed to 400 the file authorized_keys in the N900.
(I originally had copied the id_rsa.pub file ssh'ing as root and chown'ed the file to user:users to copy it to /home/users/authorized_keys. )

Now I can ssh in as `user' and I don't get prompted for the password, only the passphrase for the public key.
I plan to edit sshd_config to have
PasswordAuthentication no
PermitRootLogin no

I will also try installing rootsh to become root if necessary.

Thanks,