Hi,
Only the following events trigger Cisco Unity Connection to turn MWIs on and off:
> When a message for a user arrives on the Cisco Unity Connection message store, Cisco Unity Connection notifies the phone system to turn on an MWI on the phone for that user.
> The MWI remains on even after the user listens to the message. It remains on until the message is saved or deleted. Once the message is saved or deleted, Cisco Unity Connection notifies the phone system to turn off the MWI on the phone.
> When MWIs are synchronized, Cisco Unity Connection queries the message store to determine the status of MWIs on all phones, and resets the applicable MWIs.
So, unfortunately your requirement does not look feasible with Unity Connection.
HTH
Manish