Alex you say service port and cbx monitor. Are you sure your talking about a Hicom 9006.5 PBX? Or are you referring to a ROLM 9005?
If you referring to a Hicom 9006.5, use ADD-BCSM:UNIT=A1,TYPE=DPP,LINE=9,RMX=N;
DPP Line 9 is for the CCA modem.
If your referring to the ROLM 9005, use LI PORT...