This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
I am not sure how the soapUI works, but do you use glassfish as a server?
Does the exception reach your client? Just put a try-catch statement around the web service invocation and see if you get the AddNumbersException? The exception should generated by wsimport if it is mentioned in your WSDL.