I've actually had this happen to me on more than one occasion, but after the first couple (heart-stopping) times and someone told me that it was working for them, I figured it was more on my end.
More often then not, the time it takes to momentarily panic, calm down, and then check my e-mail or something is usually enough time for me to be able to get re-entry
That or I go play WoW...
But it IS good to know that I'm not the only one with this issue, and next time I think I'll follow them thar steps. Probably more efficient than my way, anyhoo.