Clearly Rihanna is able to forgive and forget.

The singer posted a remix of her Talk That Talk album track, 'Birthday Cake' on music sharing sites before heading out to celebrate her 24th birthday last night.

Not weird at all you might think. Well this remix also features a certain ex-boyfriend, Chris Brown. You know, the Chris Brown who beat her up on the eve of the Grammys in 2009?

It seems that the pair have become friends again.

Yesterday, Chris wished Ri-Ri a happy birthday on Twitter. A few hours later she asked who wanted "cake" to which he responded: "Cake, cake, cake" along with a link to their remix of the song. 

Listen to 'Birthday Cake' below. Warning: Very explicit and generally questionable.