java.lang.NoClassDefFoundError: Could not initialize class com.sun.xml.internal.ws.fault.SOAPFaultBuilder
I was running gwt application on tomcat server and here is the error I encountered. After fighting with this error for some time I resolved this issue by deleting the jax-impl.jar from the tomcat lib folder. It was a possible conflict of the jaxb jar versions with one of my webapps installed in tomcat.