Thanks. However, I've tryed with your .jar but I still have the save problem. Here is the error :
java.lang.NoClassDefFoundError: sun.reflect.ReflectionFactory is a restricted class. Please see the Google App Engine developer's guide for more details. at com.google.apphosting.runtime.security.shared.stub.sun.reflect.ReflectionFactory.<clinit>(ReflectionFactory.java) at com.thoughtworks.xstream.converters.reflection.Sun14ReflectionProvider.getLazyRefectionFactory(Sun14ReflectionProvider.java:105) at com.thoughtworks.xstream.converters.reflection.Sun14ReflectionProvider.getMungedConstructor(Sun14ReflectionProvider.java:97) at com.thoughtworks.xstream.converters.reflection.Sun14ReflectionProvider.newInstance(Sun14ReflectionProvider.java:76) at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.instantiateNewInstance(AbstractReflectionConverter.java:313) at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:162) at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:82) at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:63) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:76) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:60) at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:137) at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:33) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:965) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:950) at com.thoughtworks.xstream.XStream.fromXML(XStream.java:893) -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.