guivarrichio and skaterfou, if you guys have the nano-lookalike player similar to bladgum then there's a lot of firmwares for that kind of player floating all around. In fact, there are some on this site...3.2.16 and 3.3.35 I believe.
Also have a look at the firmwares on
http://s1mp3.org if you haven't already.
Check those out and let us know if you find the correct firmware.