I'm using IB's TWS and in the past any time I did a straight buy or cover order on a short where I gave a limit price 5 cents or more outside of the ask/bids, TWS always waited until it could find my price before executing. But when I did the same thing on a short -- giving a limit price about 20 cents outside the ask/bids (I only wanted to go short if support was broken) -- TWS instead seemed to execute at the market. Is this an IB issue or normal behavior?