q: standalone authentication

hi,

i made a rails2 app with authentication a while ago for a friend
(rails2 + restfulauthentication) . now he wants me to another one.
userbase is the same. now what the best to have only one
authentication system and have the 2 apps "looking up" credentials etc
on the authentication system?
should i look into engines? any ideas?
thx

You can try something like this:

https://github.com/hasgeek/lastuser

May be use that one itself.