Thread:Extension talk:LiquidThreads/How to assign the "LT edit right" to the specific group, which has only "read" right

Hi all, I have LT extension installed. It works fine, but I have a question. Does anyone know how to assign a right to edit (Start a new discusion) to a group, which has the only right to read pages. When I set $wgGroupPermissions['user']['edit'] = false; it automatically removes the link to Start a new discusion feature. I want to allow this group to Read all pages and to Edit only Discussion page.