I don't get that problem If I try to order more than in stock, it tells me. It is supposed to tell you (or the customer) exactly how many are in stock at that point (in the shopping cart), but that part isn't working for me.

I have "alllow checkout" (when stock is unavailable) set to false. Do you have that?? It's under Configuration>>Stock>>Allow Checkout. If that doesn't fix it, I'm not sure what else the problem could be.

Michele