php auth

[millw0rm]

I am about to implement an authentication system on the site I am
building. Basic feature i need are

1. Email authentication
2. Capcha verification
3. Session management
4. Redirect (If user is not signed in present signin page n after
successful login push the user back to the previous page)
5. Cookies

i was thinking of phplib but it contains too much of classes n
functions i dont need all of them, jst basic will do...

u guys know of nething which can do the job????

thnx