I am the Tech Director for a school district. We use a product called SchoolMessenger (SM) to automatically call homes with attendance information, lunch account balances and routine notifications. Currently, we have a dedicated PRI line plugged into a Sangoma A101 card in the SmartCall (Linux) box. We are investigating running SM through the 3cx PBX and using SIP trunks. SM supports a SIP connection to most SIP compatible PBXs. SM tech support said the SIP standard is somewhat variable and told me to answer this question: Does 3cx support 3rd part answering supervision? Worded another way: Does 3cx report the call back as answered when the called party actually picks up the phone? Any help would be greatly appreciated.