BlackBerry Partners Fund, a joint venture between BlackBerry-maker Research In Motion, JLA Ventures, and other investors, is moving aggressively into China with a new $100 million fund.

You can read the announcement at the new BlackBerry Partners Fund China website. The big message is that China’s mobile market is already the world’s largest, it’s still growing quickly, and the BlackBerry fund wants in on the action. For local expertise, it’s partnering with China Broadband Capital Partners, a firm that was founded in 2006 and focuses on media and communications investments. The new venture will have offices in Beijing, Shanghai, and Hong Kong.

The BlackBerry fund was first announced in May 2008, shortly after the unveiling of the iFund from Kleiner Perkins Caufield & Byers, which focuses on iPhone investments. At the time, JLA partner Rick Segal told us that while the fund would invest in companies that build applications and services for BlackBerry devices, they wouldn’t have to be BlackBerry-only. The fund’s portfolio companies include location-based service Buzzd, traveling aid WorldMate, and social email startup Xobni (the Xobni app is pictured).

Kleiner also increased its investment in the iFund recently, doubling it from $100 million to $200 million.

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