Alot of people are abusing the ghost trade system setting up fake trades on the market. The exact problem is when you have a gold offer and a item for the same item. If someone accepts the gold offer, the existing item offer remains, and if you accept the item offer the existing gold offer remains. There is another bug is if you accept someone else's offer with your item, your existing item transactions remain. I believe it should be a simple fix because you already have the code in place to remove other item offers if the item is sold. You could just run a remove all items with that uniqueitemID for both the sold item and requested item on the market db every time a transaction is completed.
The abuse happens is when they get their friends to setup fake trades. The have an item they want to sell at an inflated price and the place a +2 item for that +1 item. Afterwards the place stones up for their +2 item and they have a nice scam in place. Someone buys their +1 item to get the +2 and when they click on the +2 its gone.
