exten => <voicepulse number>,1,Answer
exten => <voicepulse number>,2,ResponseTimeout,5
exten => <voicepulse number>,3,DigitTimeout,2
exten => <voicepulse number>,4,Background,some_prompt

exten => 1,1,Dial,SIP/bob
exten => 2,1,Dial,SIP/tom
exten => 3,1,Dial,SIP/joe