Go app manager and install microemulator; go to desktop, open microemulator, you can then open your .jar file within miroemulator box. The microemulator look at your 3.5 inch N900 screen as a regular desktop screen, i.e, 15 in monitor, so everything is very very tiny , still waiting for some guru to teach how to change the scale of this thing, other than that, I have yet to run a .jar program NOT working. and again, speed is like any maemo apps, almost eye-blinking fast, you cannot really sea anything that small, but you can hear the thundering noise of racing car games. Enjoy,

bun