http://en.wikipedia.org/wiki/Dimps

Dimps is an Osaka-based development studio with an additional office in Tokyo, Japan. Employing a staff of 218 people, it is known for developing such games as the Dragon Ball Z: Budokai trilogy for the PlayStation 2, and the Sonic the Hedgehog games specific to the Game Boy Advance and Nintendo DS under the guise of Sonic Team. It also co-developed Tales of the Tempest on the Nintendo DS with Namco Tales Studio and co-developed Street Fighter IV with Capcom. The company was founded by several former SNK employees, including Street Fighter co-creators Takashi Nishiyama and Hiroshi Matsumoto.