I have the following setup.
Siemens PABX - VG30D DPNSS/QSIG Converter - 2811 MGCP GWay - UCM V7.1.3 Cluster
The scenario is:
IPT Ext 8100 and 8101 are in a Call Pickup Group.
PABX Ext 2000 calls IPT Phone Ext 8000. Ext 8000 transfers call to an IPT Phone Ext 8100. Ext 8100 rings and the Ext 8101 uses Group Pickup to answer call.
The call is connected, however after 13 seconds Ext 8101 is disconnected. The originating PABX Ext 2000 now hears ring tone.
Debug ISDN Q931 on the Gateway confirms that a disconnect is received from the PABX.
PABX traces confirm that when the call is picked up by IPT Ext 8101 the PABX sends an optimisation message (110B), however this is being rejected by the Call Manager message (54).
Any suggestions would be appreciated.