probably it'll be some kind of challenge and response mechanism (like ftdi driver send some random bits as challenge, FTDI chip, which is nothing else then a glorified special purpose microcontroller calculate a math function (most probably a hash of some sort) and then spits the answare back to the PC, so is a bit more complicated than just changing a couple of masks
that sais it's not that difficult to reverse engineer the function given enough time with enough math and silicon reverse engineering capabilities as you said i totally expect chinese to change slightly the design and make use of said driver...
DRM (to which this is related) has never, ever, ever worked, it might fend of random casual joe blog's kind of counterfeiters, but chineese industry is not that easy to fool...