Thanks Addison, I'll check the Xkbd version I have installed and see if there's a newer one around

Uhm, the xkbd package in Rubybox repository is xkbd_0.8.15m-2_armel.deb, that's exactly the one downloadable from http://pupnik.de/xkbd.html
Oh, well, I'll just remove everything ruby/dosbox related and start over