Comment by dominik.mayer:There are no exceptions thrown if the Proxy uses "boolean" and the Entity "Boolean". It just doesn't work. I found the error by switching back to 2.1.0 which does throw the exceptions.
For more information: http://code.google.com/p/google-web-toolkit/wiki/RequestFactory_2_1_1 -- http://groups.google.com/group/Google-Web-Toolkit-Contributors
