To rccarracer: the signature is signed and dated 25 (if not 24) August 2002 (Indonesia Reedy Race) by him and his father.
Some of other local racer also has his signature including "Keyence" I believe.
Moreover, some Xray and other brand drivers also ask him to sign on their body shells.
Anyway, he is coming again as Team Mugen Indonesia for the upcoming 1/8 International race next week.