I picked up a RAMPS bundle off dx.com a few months back, and finally got around to using it yesterday. I have noticed that it is impossible to change the micro stepping on the board, since there is continuity between both sides of the jumper blocks (with an unplugged board, without jumpers or drivers) and +5v line. I did a few searches and I haven't seen anything about anyone else encountering this, but I suspect there are other boards like this out there.

See here.