For a while now I've been thinking about trying my hand at creating a game similar in spirit and execution to Baldur's Gate, Icewind Dale and offshoots. I'd rather not face the full bulk of work in implementing my own RPG system - I'd like to use D&D rules.

Now, reading about the subject it seems there is something called "The License" which allows a company to brand a game as D&D. This license seems to be exclusive, and let's just say I don't have the money to buy it :p.

Is it still legal for me to implement and release such a game? Commercially or open-source? I'm not sure exactly which edition would fit the best, but since Baldur's Gate is based of 2nd edition, could I go ahead an implement that?

in short: what are the issues concerning licensing and publishing when it comes to D&D?

Also: Didn't see any similar question...