Thanks CountRaven for the answer.

I've tried all these programs you mentioned; using the legacy MOS 1.4 keymap I managed to get Greek characters on some text boxes but mostly it shows accented characters (e.g in OWB). The problem - this is just a suspicion - relies to the legacy keymap not supporting Unicode (I think MOS 1.x did not provide Unicode support).

It's a shame such a nice system does not work - regarding keymaps - as advertised. Why on earth they included a Greek PC 104 keymap that does not work with anything?