pear Auth and cookies

Hello, I have a hopefully simple question. I am using pear auth to help with my authentication on my website. However, I want a feature to keep the user's username for the next time they visit; so they don't have to login each time. Is there a way to integrate this into the auth object? I have not been able to find anything. What I mean is, if I create the cookie, how can I have auth accept that kind of like a login? or in other words create the session data when it sees those cookies? I thought there must be a way since pear classes generally cover about every desirable effect you can think of. :) Sorry if it takes me a while to reply to any responses; if the reply isn't both to the list and to my e-mail I don't get it for a while since it is hard to check the list page. Brandon