According to some goons over at SA, Arino won a Doraemon-trivia contest and got to appear as a guest star on an episode of Doraemon. Picture GET:

http://i54.tinypic.com/123ul2f.jpg

The contest was part of some variety show; the episode itself can be found here:

http://v.youku.com/v_show/id_XMTA0OTg2ODE2.html

But there's no subs, so unless you're fluent in moonspeak, you're sunk until SA decides to focus on extra-canonical Arinobilia.

Doraemon is wonderful. It's a real shame it never came over to the United States. It's also strange, seeing as how it's apparently reached every single other nation on the planet.