Cocos2D-X started supporting BlackBerry PlayBook in Mid-January 2012 with the 0.11.0 release. Releases after that fully support the platform, as shown by the changelogs in 0.12.0 and 0.13.0 beta.
If you are interested in using Cocos2D-X on the PlayBook, download it directly from cocos2d-x.org
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