As part of 2012
Spring Seller Update, eBay has introduced Business Policies to
streamline the listing process and make it very easy for sellers.
You can find more information for API changes on the eBay Developer Product Updates page.
If you would like to opt in your Sandbox user for Business Policies, please click the 'Business Policies Sandbox Opt-in' link mentioned under the 'Sandbox Environment' heading in the doc : http://developer.ebay.com/Devzone/business-policies/Concepts/BusinessPoliciesAPIGuide.html