Is it possible to have the message waiting indication appear on multiple/all phones for a single voicemail box?
only way to accomplish this is to monitor the mailbox in a Status Group and apply that to the phone. The MWI will not light up on the phone but the line button with be blinking or on indicating that a message is in the mailbox.
Refer to this config guide for more info: https://supportforums.adtran.com/docs/DOC-2260
Hope that helps.
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