AT&T 8503T - Manual (Page 9)

Send All Calls Temporarily sends all your calls to the extension of a person
designated to answer them when you cannot (perhaps a secretary or receptionist).
Use when you will be away from your desk for awhile, or when you do not wish
to be interrupted by voice terminal calls.
Voice Message Retrieval Gives you messages (via computerized voice) left for you
through Leave Word Calling or as typed by a covering user. If authorized by your
System Manager, you may also retrieve messages for one or more of your co-workers.
Use to hear all messages received while you were away.
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