This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
The result you get is a web page. I advise you to take a look at the server logs to see if there are more information about the error there.
Also make sure that the web service has been deployed successfully.