O button work like back button in most emulators!

Hello people


First I love my xperia play and I feel sad that no company done another cel like this with hidden buttons =\

. Recently I installed some emulators from google play like mame, Final burn,etc
and the O button works just like the back button from our phone and that makes the emulator close as usual. There's no config in changing this in emulators config options. I can let the O button as blank if I want, but I want use it!

For example: Street fighter 2 has 6 buttons in arcade weak punch, mid punch, strong punch, weak kick, mid kick, strong kick.
I want use all my 6 buttons in my xperia play to be like this
weak punch -Square
mid punch - L
strong punch - Triangle
weak kick- X
mid kick - R
strong kick - O

but if I press the O button, the emulator close instead simulate the strong kick.

Anybody knows how to fix thix?
I heard that in other android games(no emulators) this happen too.

Thanks and Long live our xperia Xd