It needs to have a "VX4" or "VX5" circuit board. It's some white text printed on the circuit board itself. I don't know of any way to tell without opening up the controller and looking to see what is printed on the circuit board.
Unlike the Matrix2 and Microsoft XBOX360 controllers, however, all the PS3 controllers we have been purchasing from all our suppliers are coming with VX4 or VX5. That includes Best Buy, Costco, Walmart, Gamestop, D and H distributing, etc.