Here in Taiwan a Prius driver (who is also a car service specialist within the foreign community) claims Toyota (a local representation) has told him, the Prius (that is the hybrid car) would have had a software bug which has caused the unwanted acceleration and this software bug already got fixed by a software update. To my knowledge Toyota has not yet admitted there is such a bug and probably never will. No-one can make sure what "some Toyota garage guy" in a Taiwanese Toyota rep. might have said is actually true, of course and I am not making any statement in this direction.
http://forumosa.com/taiwan/viewtopic.php?f=75&t=85671&p=1125473#p1125473
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