I get this error when I compile using the gxt.jar file that I downloaded from this site.
OS: Windows XPbad class file: F:\Isaac\AdminClient\gxt-1.0-beta1\gxt.jar(com/extjs/gxt/ui/client/mvc/AppEvent.class)
class file has wrong version 50.0, should be 49.0
Please remove or make sure it appears in the correct subdirectory of the classpath.
IDE: Netbeans with GWT4NB plugin
(I have compiled with MyGWT 0.5.2 using Netbeans, so I don't think that's the problem.)