This happens to me in firefox but not in IE. In fact, sometimes it happens in only a couple minutes. I hate it.

Road Fan--remember to copy your posts before you submit them (highlight text - Ctl-C). Then if you get timed out, you can paste the post in the Quick Reply form after you log back in (Ctl-V).

Also, for me anyway, the BF server will hold onto my post if I have typed it into the Advanced form rather than the Quick Reply form.