Samsung WIP-5000 - Manual (Page 40)

BASIC FEATURES
Page 22 © SAMSUNG Electronics Co., Ltd.
Call Camp on
When you call another internal station and receive a busy
signal, you can give the called station an off-hook ring tone
and wait for a little while.
Call Back
If the other party is busy, you can reserve a busy station
callback. When the busy station becomes free, your phone
will ring. If you receive the call, the other person’s phone will
also ring.