Steven M. Bellovin writes: 

> Hmm -- you could try removing the battery for a few minutes, to reset
> everything to the default state. 
> 
> Other than that -- perhaps try installing a hard drive and a CF card
> and see which boots....

Sorry if I wasn't clear.  I can boot the thing (build IDE disk on another, 
sorta similar platform and boot), but I don't know what the jumpers mean and 
it all leaves me having to pull the thing out of the rack and opening it up 
if the simplest thing goes wrong.