[SIPTRUNK1]
exten => s,1,SetCallerID(${CIDNUMBER})
exten => s,2,SetCIDName(${CIDNAME})
exten => s,3,SetGlobalVar(SIPTRUNK1=${SIPTRUNK1}+1)
exten => s,4,Dial(SIP/${EXTEN:1}@SIPTRUNK1)
exten => s,5,Hangup
exten => s,6,SetGlobalVar(SIPTRUNK1=${SIPTRUNK1}-1)