>Upgrading from 1.4.1 the the latest current snapshot fails at the [mydisk]
>prompt. Something is displayed, then the screen clears, and then the
>[mydisk]: prompt appears once more. Typing something in and hitting return
>yields a root prompt.

I had the same thing happen with last weekends source snapshot.  Grabbing
more recent sources the problem went away, so you could wait till this weekend
and grab the next snapshot or grab the current source by some other means.

cheers
mark