Have you defined any custom calculations in the cart? or added any discounts, charges, taxes or shipping rules?
If so can you post back what they are?
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.