extensions_additional.conf
[ext-fax]
include => ext-fax-custom
exten => s,1,Macro(user-callerid,)
exten => s,n,Noop(Receiving Fax for: ${FAX_RX_EMAIL} , From: ${CALLERID(all)})
exten => s,n(receivefax),StopPlaytones
exten => s,n,ReceiveFAX(${ASTSPOOLDIR}/fax/${UNIQUEID}.tif,f)
exten => s,n,ExecIf ...

