[from-xs4all]
exten => s,1,Answer
exten => s,2,Goto(password,307,1)

[password]
exten => 307,1,Ringing
exten => 307,2,DigitTimeout(4)
exten => 307,3,ResponseTimeout(5)
exten => 307,4,Read(mycode,vm-password,3)
exten => 307,5,NoOp(${mycode})
exten => 307,6,Gotoif($[${mycode} = 123]?2:7)
exten => 307,7,Hangup