Bruce, G-money was exactly right above, and all his points are relevant to your initial post.
Short selling:? IB handles a lot you are not accounting for:? When you short a stock, you borrow it from someone else via a security lending program (and pay an ongoing fee to do so).? You then sell the stock in the market (that is how you get the cash).? But you have the obligation to return the stock at some point, plus pay any dividends the stock pays along the way.? You absolutely have to pay the dividends.? The person you borrowed the stock from gets the dividend money, some of the borrowing fees (rest to their broker), and eventually their actual stock back (so basically a little better off than just holding the stock).
Again, those borrowing fees are not interest, so you should find out how much you paid in those.
