really need help with buttons

[white31]

Sorry I didn't explained accurately. I want to use all back buttons on the gamepad - LT, RT, LB and RB but problem is the game itself doesn't support more than 1 pair of shoulder buttons as I understand, because PSP has only one pair of L and R. I have already set L as X+O (from Tekken 2 example which is both legs) and R as square+triangle (both hands), so now there are no buttons left to set grabs which are square+X and triangle+O and I play without grabs now, that's where I need help, I want to add these buttons to the game somehow so I could use gamepad as in a console Tekken.