Core Issue
In the Cisco Unity 4.x, if there are multiple e-mail addresses separated by a comma, listed under Text for Cisco Unity Inbox then the message notification only goes to the first e-mail address. The rest of the e-mail addresses remain undeliverable.
Resolution
By design, Text for Cisco Unity Inbox allows message notification to only one e-mail address. In order to send notification to more then one recipient, configure Text Pager 1 and Text Pager 2 instead of Text For CiscoUnity Inbox with separate e-mail addresses.
Refer to the SMTP Message Notifications section of Setting Up Message Notifications for more information.