This is stupid. The islands have been in Japanese control (and US control) for some time now. Seems to me China signed away it's rights to the islands in 1895 with a treaty. Also seems to me that Japan bitch smacked China around in the 1940s, and eventually the islands were under US control at the close of WWII. The US turned control of the islands back over to Japan in 1970-something.
Sure makes for some interesting reading:
http://en.wikipedia.org/wiki/Senkaku_Islands_dispute
I think Japan has some issues with Russia too about some islands.
http://en.wikipedia.org/wiki/Kuril_Islands_dispute
With the Kuril islands, it seems Russia took the islands by force at the close of WWII, and then Japan gave up all rights to the islands in the San Francisco Peace Treaty.