Unify OpenScape 4000/HiPath 4000 - Call forwarding for internal;external; Using callback

Basic functions 39
Call forwarding for internal/external
r The key LED lights up.
Only the call forwarding icon is displayed.
Using callback
Storing a callback
Prerequisite: The internal station called is busy or nobody answers.
Confirm the option shown.
Accepting a callback
Prerequisite: The internal station called was busy. You have saved a callback.
Z Your telephone rings.
^ Lift the handset. You hear a ring tone.
or
n Press the key shown. You hear a ring tone.
Cancel call backs
Confirm the option shown.
or Do not answer the call. After ringing four times, the callback is canceled.
K
There is no display message for the call forwarding types "Busy", "No answer" and
"Busy/no answer". The LED key does not light up.
If your phone belongs to an ONS group (parallel call  page 104), please
note the following:
Callback on busy is only signaled on the busy phone, not in the whole ONS
group.

Callback on no reply is entered in the mailbox ( page 24) on all internal
system phones in an ONS group.
Callback?
If the called party was busy, the callback is automatic.
If the called party did not answer, a message is left in the called party’s
mailbox.
If the party has activated call forwarding ( page 35), you will receive the
callback from the call forwarding destination.
Cancel callback?