Comment as a new forum topic.

Hi
I spent last few hours figuring how to set up that first comment in article create new forum topic, so replies in this article sholud be also replies in new forum topic. As I see when I add new comment to article it stay as article comment and I absolutely don't know how to link it with forum. I've installed even advanced forum, hoping It give me more settings option for linking content/node comments with forum post. Well I think it is very easy to archived and I feel I miss something obvious but maybe I'm wrong. Can anybody help me with this ?