In Groove there is no way to do it, unless u create a workspace and invite
that contact to it.
For Those who have access to Groove 3.1 SDK:
Can there be any message filtering plugin be written with that SDK? And
say message which so and so subject will be redirected to that plugin and
it shows them as a chat message.
Thanks for asking this. From this requirement I came to know I need to
provide such Message Filtering functionality in Collaber.