Feature
(While busy, DND or call tone is heard/after dialling)
Default
Joining an Existing Call (Executive Busy Override)
3
Leaving a Message Waiting Indication/Calling Back the Caller Who
Left an Indication (Message Waiting)
4
Monitoring Another Extension (Call Monitor)
5
Reserving a Busy Line (Automatic Callback Busy)/ Setting
Callback on an ISDN Line (Completion of Calls to Busy Subscriber
[CCBS])
6
1.2.6 Alternating the Calling Method (Alternate Calling—Ring/Voice)
Feature
(While dialling or talking)
Fixed Number
1.4.5 Multiple Party Conversation
Adding Other Parties during a Conversation (Conference)
3
1.11.1 If a Doorphone/Door Opener is Connected
From any extension while talking to the doorphone 5
5.3.1 Feature Number Table
356 Operating Manual