Hi robs87,

You haven't explained why you need this kind of SSH connection like you described here. Doing so would help in that maybe there is an easier solution to the problem you're trying to solve. For example, have you considered something like telnet+SSL?

I haven't worked much with OpenSSH so this is just an educated guess, but you might want to look into PAM (pluggable authentication modules), I believe OpenSSH can be configured to use custom PAM modules which might give you the ability to have OpenSSH authenticate with something other than UNIX accounts.

Hope this helps,
-- Hauke D