Just thought I'd pass on some news about use of foreign bank ATM/Debit cards in Japan.
As of April this year, 7-11 ATMs, which use to allow foreign country's ATM cards, no longer accepts MasterCard, Maestro, Cirrus or Star System ATM/Debit cards. This includes the 7-11 ATM in the basement of Ikspiari.
The ATM in TDL Mitsubishi Bank in World Bazaar for me only accepted a Chinese bank.
I ended up using the tried and true ATMs at the Post Offices.
If you don't want to end up short of cash I suggest you do your research before traveling to Japan.