On 27th the rating company S&P has lowered the rating for Japan's long-term governmental bonds to "Double A minus". It is understandable, because the volume of official debts in Japan is twice as big as annual GDP (though Japan's governmental bonds are consumed almost entirely within Japan. The question of default, thus, does not loom).

But I do not understand why Japan's bond is rated lower than the Spanish one, the value of which is now sustained by Japan's active purchase of EFSF (The European Financial Stability Facility) bonds (Japan has bought 20% out of 5 billion Euros initial issue).
If Europe's economy is sustained by fragile Japanese economy, then it is certainly time to short Japan as well as Europe.