AT&T MERLIN LEGEND Release 4.0 Feature Reference page 187

Feature Reference
If an operator wants to turn on the message-waiting LED to indicate that a
message is waiting, the operator first checks the LED next to the recipient's DSS
button to determine whether or not the recipient's message-waiting LED is on;
the operator's lights do not light when a message-waiting LED was turned on by
another source, such as a fax machine or another user. To leave a
message-waiting indication when the LED is off, the operator presses the
programmed Send/Remove Message button, followed by the DSS button or
Auto Dial button for the person for whom the message is intended. The operator
presses the Message Status button to return to normal call handling.
By pressing the Feature button and selecting
DLC operators can leave a message at another extension. This does not
however affect the Message Status operation, because Message Status only
shows messages sent with the Send/Remove Message button. See
"Messaging" for more information about sending and receiving messages.
For calling group or CMS supervisory operation or for Hotel Extension Status in
Message Status operation, the red LED next to a DSS button for a user
extension indicates whether or not a message has been sent by any of the
operator positions. On a button for a calling group extension number, the red
LED indicates the status of the queue. For a DSS button storing a pool dial-out
code, the red LED indicates trunk availability. The meanings of the red LEDs
next to the DSS buttons while the operator position is in Message Status
operation are shown in Tables 14 and 15.
Table 14. LED Meanings for Hotel Extension Status Operation With Message Status
Active
LED Status Extension Type
Off Individual
On Individual
Off All other types of
extensions
Meaning
A system operator has not turned on the
Message LED.
A system operator turned on the Message LED to
indicate a waiting message.
No meaning
Direct Station Selector: MLX
from the display, MLX
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