A2billing / Asterisk / Http post / MySQL

hi i need an expert in helping me to install a ANI callback module for a2billing. there will be 2 stage to this installation Stage 1 ANI callback will be trigger by calling an access number with another asterisk [login to view URL] a2billing will perform like any other callback server. <Accessnumber> Asterisk(A) > SIP > A2billing (Callback) the flow will be. 1. call an access number 2. callerid is deliver to a2billing via Asterisk(A) 3. A2billing authenticate the callerid 4. use the predefine trunk in a2billing and call the caller. 5. Caller snswer the call, press DTMF for destination. 6. a2billing announce balance and time remanining for the call. 7. end of call please refer to [login to view URL] for stage 2 Thank you