IS it possible to create the 3CX phone system under the current PBX phone system which is using LG Nortel aria 300 PBX? we want to create a small 3CX phone system inside the current LG PBX phone network which means we want to use2 lines of the current extensions to connect the VoIP gateway of 3CX phone system. BUt we are not sure if this plan can be accomplished because according to 3CX system manual, VoIP gateway should be connected to PSTN lines. is it possible to connect our company's extension lines to 3CX phone system through VoIP Gateway??