For some reason, when a customer enters a new address in their address book, and then selects this as the shipping address, when they come to the final screen before payment, it has reverted back to the billing address as their shipping address. I even tried making the new address the primary address, and it still reverted back to the billing address. So, currently customers cannot use an alternate shipping address.

I am using ZenCart 1.3.8a. You can try it out at this site: www.simplycheese.net/store. I'm not sure where to look to fix this. Any help would be greatly appreciated.