I don't really understand what ldap has to do with this. These are groups that are created in Domino and are only available in Lotus Notes.
When I search for a public group in Sametime (see screenshot: http://i.imgur.com/BhpnHIV.png
), the description stays blank.
When I search for the same group in Domino Server, the description is correctly added. So I don't understand why it doesn't show up in Sametime.