I have updated the firmware on my Samsung GT-s5570 to Android 2.3.4. Google Play does not recognise that I have upgraded and will not install apps that are for 2.3 or higher. Still thinks phone is on 2.2.
I have the same phone and the same problem, running android 4.2 (flash), so google play does not watch your Firmware level, but your phone's name. Just try to find your apps on the internet or try other markets (like GetJar).
Just now I was trying to find a solution for the problem :)