[default]
include=sipp
exten => 100,1,(SIP/100)
exten => 200,1,(SIP/200)
[sipp]
exten => _1NXXNXXXXXX,1,Set(CDR(accountcode)=123456)
exten => _1NXXNXXXXXX,n,Set(CDR(amaflags)=BILLING)
exten => _1NXXNXXXXXX,n,Set(CDR(userfield)=${CALLERID(num)})
exten => _1NXXNXXXXXX,n,Dial(SIP/200/${EXTEN:1})