This extension now merged with Front End PM PRO. Buy Front End PM PRO to achieve this functionality.
This extension allow admins to create group with unlimited number of users and users can message to that group.
How to Configure:
Please go to Dashboard > Front End PM PRO > Settings > Recipient > Groups to create groups and maintain group members. Also you can set how groups will be shown to users, as dropdown or radio button.
Screenshots:
This extension now merged with Front End PM PRO. Buy Front End PM PRO to achieve this functionality.