The IncompatibleRemoteServiceException should go away when you update gwt-servlet.jar in your war/WEB-INF/lib folder. It must match the version you have used to compile your application.
You have compiled your app using GWT 1.5 (GWT-RPC version 5) and your server still uses gwt-servlet.jar from GWT 1.2 and thus expects GWT-RPC version 2. -- J. -- You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To unsubscribe from this group and stop receiving emails from it, send an email to google-web-toolkit+unsubscr...@googlegroups.com. To post to this group, send email to google-web-toolkit@googlegroups.com. Visit this group at http://groups.google.com/group/google-web-toolkit?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
