after long search, i fouund a solution using virtual joystick (ppjoy)
this link contains what i need

https://github.com/dumbledore/FlypadJoystick

and this youtube link show a demonestration but using pattern recognition instead of iphon

http://www.youtube.com/watch?v=zXJb8kkngJQ

Thank you very much

but can you guide me on from where to start or on what should i serach for and how directx can deal with gamepad or joystick
or if possible is there any java api for connecting with directx.

This is my idea, i'm planning to substitute the gamepad with iphone, i'm going to use accelerometer in the iPhone to send messages to the compter.(i'm planning to play "Need For Speed" using IPhone) .
I was able to read inputs from the iphone and i want now to dispatch the event to the operating system, is this possible in JInput or not, or is there any other solution for this and if possible is there any sample code for that, cause i was searching on the net for days and there is not enough documentation but the API docs