What I would like to do is to access my intercom line from a outside line. For example, to call in on my voip number and be connected to my 1a2 key intercom line to control relays. Any type of device that will do this? I could program my Nortel BCM 50 to answer on a dedicated line and ext and have that ext forward to another line where I do have my intercom connected but I would like to see if I could do with out the Nortel if possible.