As I replied to your message, I got another example. In my original display of the thread, I only saw your original post, Garrett's reply and your reply. When replying, I saw that Barbara has sent you a message (by the check box at the end of the reply form). I refreshed the list and Barbara reply never showed up on the thread. I can only access it by viewing the map of the thread.

>You are not alone. I often get the same problem. It occurs more often on monday, when I didn't log on on the weekend.