According to the latest issue of Japanese publication Dengeki Playstation magazine, the Dual Shock 3 controller will be compatible with Gran Turismo 5 Prologue. An image at the official GT5 website in Japan suggests exactly the same thing, that the new rumble enabled controller wil be available in October.

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The rumble-equipped successor to the lightweight SIXAXIS is almost ready for release. According to the latest issue of Japan's Dengeki PlayStation magazine (quoted over at NeoGAF), the Dual Shock 3 will be compatible with Gran Turismo 5 Prologue.

And looking at the image above, taken from Sony's official Japanese GT5 site, it seems clear that the new controller will become available in Japan at the same time as GT5 Prologue itself: this October. Which is little over two months away.