SB and ZA 5.xxx.xxx

Read on some other post that ZA 5.xxx.xxx does not work with SB. In fact all that you can do is HOST, rather than join a game.Is there a FIX to this on the horizon or is just a feature.I dont really want to go back and download ZA 4.xxx.xxx unless I have to.If this is off topic for this forum then accept my apologise.Cheers.Andy.