Socket.io authorization function is not updating session data

I'm trying to use Socket.IO's authorization function to get session data. The problem is that even if I log out and destroy my session, Socket.IO still has the old session information, which is clearly not ideal. Any ideas what I'm doing wrong in the code below?

io.set('authorization', function (data, accept) {
    if(data.headers.cookie) {
        data.cookie = parseCookie(data.headers.cookie);
        data.sessionID = data.cookie['express.sid'];
        app.set('mongo-store').get(data.sessionID, function (err, session) {
            console.log(err, session);
      if (err || !session) {
                // if we cannot grab a session, turn down the connection
                accept('Error', false);
      } else {
        // save the session data and accept the connection
        data.session = session;
        accept(null, true);
      }
        });
    } else {
        return accept('No cookie transmitted.', false);
    }
    accept(null, true);
});

And here is the connection code:

io.sockets.on('connection', function(socket) {  

  var hs = socket.handshake;
  console.log('A socket with sessionID ' + hs.sessionID 
      + ' connected!');
  // setup an inteval that will keep our session fresh
  var intervalID = setInterval(function () {
      // reload the session (just in case something changed,
      // we don't want to override anything, but the age)
      // reloading will also ensure we keep an up2date copy
      // of the session with our connection.
      hs.session.reload( function () { 
          // "touch" it (resetting maxAge and lastAccess)
          // and save it back again.
          hs.session.touch().save();
      });
  }, 60 * 1000);
  socket.on('disconnect', function () {
      console.log('A socket with sessionID ' + hs.sessionID 
          + ' disconnected!');
      // clear the socket interval to stop refreshing the session
      clearInterval(intervalID);
  });
});