The link you provided is for 1.11 rev 356
There is no official version 1.20 out now. For some reasons (ask the developers) you get version 1.20 if you compile latest PMS beta source code. Here in latest beta thread it is still called 1.11(.xxx)
Finally 1.20 is the same as 1.11beta. The exact version ist described by revision number. Latest rev-nummber is 358 at the moment. Have a look here: http://code.google.com/p/ps3mediaserver/source/list
So I gave you the correct link...