Using the OpenPOP .net client for getting messages from Gmail.

I'm wondering how I can get only the new messages?

Currently, I get the atom feed and then get as many emails as the feed has with the OpenPOP client (starting from the first).

    GmailAtomFeed feed = new GmailAtomFeed("user", "pass");
    feed.GetFeed();

    int unread = feed.FeedEntries.Count;

    POPClient client = new POPClient("pop.gmail.com", 995, "user", "pass", AuthenticationMethod.USERPASS, true);



    for (int i = 0; i < unread; i++)
    {
        Message m = client.GetMessage(i, false);

        // ...
    }

Is there a better way to do this?

And how do I set the unread messages to be read?