Let's try this link instead:

Japanese draw-bored mortise and tenon detail

I have a Makita portable hollow chisel mortising machine. I brought it back from Japan with me. I could probably order another one if you twist my arm and bribe me, however you may do just as well with a General International or Powermatic hollow chisel mortiser. Usually the peg mortise is reasonably close to an arris, so any hollow chisel mortising machine that can extend out over 6" across a timber will work for most connections. I got one at the College of the Rockies and we used it for the TF course when I was working there. Just needs a couple of outfeed supports - it worked well. The Makita beam mortiser is more ideally for softwoods - trying to poke large holes through on oak is probably not going to be a good time in anything larger than 5/8". Japanese pegs, or komi sen, usually aren't much bigger then 15mm though.