Bei einem ptmp (Mehrgeräteanschluss) wird dies über Call-Deflect realisiert, bei ptp via Call-Reroute. Das war jedoch bei Patton falsch implementiert. Seit Build Series 2013-07-17 sollte es jedoch gehen (selber nicht getestet):
10977 Support for call deflection on ISDN
In addition to the call reroute facility SmartWare supports now the call deflection facility as well.
When issuing a call reroute through an ISDN connection, the type of facility is selected
depending on the layer 2 protocol. For point-to-point links a call reroute facility is sent and for
point-multi-point links a call deflection facility is sent. In the incoming direction both types of
facility are accepted, independent from the layer 2 protocol.