Regarding User Voice Response in IVRS System

Hello Friends,

                   [b]  I  Have Successfully Making IVRS System using asterisk with php agi and sangoma
                     A200 .now i want to handle user voice response during ivrs. basically i want to  
                     handle  alphanumeric chracter when ivrs system is please give me some 
                     direction how asterisk handle user voice response. for example if ivrs system               
                     prompt   for user for please enter your driving license number and license number
                     is asterisk can handle this alphanumeric data during ivrs call.
                     please advice me how can i do that.


Thanks & Regards
Ankit Jain