At the last they could implement this feature (which is trading) but you won't like how it will work. I think the only way to use it is either to separate dm into dm purchased by money and dm you get ingame, and so you can trade with items purchased by money and only that kind of items.
The other option is that you can host rooms for trading but creating a room will cost 500dm per, and so a trade will cost you dm to do per, that way you avoid abuse from this.
But as kaiser said, this won't happen not even near. The day this happens will be 1 month before the game is actually closing.