How to pass cookies to any website url?

Hi All,
I wanna pass cookies with url.Suppose i have two website and both
website have LDAP server for user authentication.if i authenticated in
one website then i wanna pass that cookies to another website for
authenticating the user.
Is it possible for single sign on?
If yes then please tell me how can i pass the cookies url.
Need your help actually i wanna do single sign on i am able to
authenticate user through mechanize but i am not getting proper url as a
authenticated user.
I hope you got my problem if not the please tell then tell me your
answer.
me and if yes .
Waiting for your reponse.
Please help me.
Thanks,
Varun kumar