On her 24th birthday (Feb. 20), Rihanna and Chris Brown release the remix to 'Birthday Cake,' a track appearing on her sixth LP, 'Talk That Talk,' and which features a surprising verse from her ex-boyfriend.

Brown dropped the 'Birthday Cake' remix on his Twitter account, posting the song directly to his one-time love interest.

Last week, The BoomBox reported that the former couple would release the song, a shock to critics who are not fond of Brown after the 2009 highly publicized domestic assault where he attacked Rihanna but a welcome effort for fans who have been waiting eagerly for the two to reunite.

Listen to Rihanna & Chris Brown on the 'Birthday Cake' Remix
'Birthday Cake' was produced by lauded songwriter The-Dream and beatmakers Da Internz.

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