[in]
exten=>server,1,Goto(s,1)
exten=>s,1,answer()
exten=>s,2,background(${SOUNDS}enter_ext)
exten=>s,3,waitExten(5)
exten=>s,4,goto(2,1)
exten=>1,1,dial(SIP/me)
exten=>2,1,playback(${SOUNDS}trying_cell)
exten=>2,2,dial(SIP/cell@server)