NEC UNIVERGE SV9100 Features And Specifications page 636

move to the next destination even if there is only one destination active.
Once the notification process begins, a new message does not restart the process if it is
already in progress. Once the process ends (e.g., if the message is acknowledged or the
maximum number of callout attempts is reached), the next new message will restart the
process.
The system determines which numbers are internal extensions or external numbers by the
system dial plan settings.
Depending on the system ARS routing maybe needed to properly route external calls.
If no trunks are available when an outside destination is attempted it is counted as a Busy
No Answer attempt.
Program 47-02-28 is used to enable or disable message notification queuing. If enabled,
message notification is stored in queue when there is no active notification destination.
Once the destination becomes active the queued notification is processed.
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