Hi, I've created a class and added a couple of properties to it via the class editor (a string and a text area). When I try to add a User list (from the drop down menu) the following exception occurs: Error number 0 in 11: Uncaught exception Wrapped Exception: com.xpn.xwiki.objects.meta.UsersMetaClass incompatible with com.xpn.xwiki.objects.classes.PropertyClass com.xpn.xwiki.XWikiException: Error number 0 in 11: Uncaught exception Wrapped Exception: com.xpn.xwiki.objects.meta.UsersMetaClass incompatible with com.xpn.xwiki.objects.classes.PropertyClass at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:159) at org.apache.struts.action.RequestProcessor.processActionPerform (RequestProcessor.java:431) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doPost (ActionServlet.java:432) at javax.servlet.http.HttpServlet.service(HttpServlet.java:615) at javax.servlet.http.HttpServlet.service(HttpServlet.java:688) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter (ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java :121) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.apache.catalina.core.StandardWrapperValve.invoke (StandardWrapperValve.java:213) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178) at org.apache.geronimo.tomcat.valve.DefaultSubjectValve.invoke (DefaultSubjectValve.java:46) at org.apache.geronimo.tomcat.GeronimoStandardContext$SystemMethodValve.invoke(GeronimoStandardContext.java:342) at org.apache.geronimo.tomcat.valve.GeronimoBeforeAfterValve.invoke(GeronimoBeforeAfterValve.java:31) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105) at org.apache.catalina.core.StandardEngineValve.invoke (StandardEngineValve.java:107) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541) at org.apache.catalina.authenticator.SingleSignOn.invoke(SingleSignOn.java:392) at org.apache.catalina.connector.CoyoteAdapter.service (CoyoteAdapter.java:148) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869) at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java :667) at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527) at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run (ThreadPool.java:869) at java.lang.Thread.run(Thread.java:799) Wrapped Exception: java.lang.ClassCastException: com.xpn.xwiki.objects.meta.UsersMetaClass incompatible with com.xpn.xwiki.objects.classes.PropertyClass at com.xpn.xwiki.web.PropAddAction.action(PropAddAction.java:59) at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:143) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java :431) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doPost (ActionServlet.java:432) at javax.servlet.http.HttpServlet.service(HttpServlet.java:615) at javax.servlet.http.HttpServlet.service(HttpServlet.java:688) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter (ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java :121) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.apache.catalina.core.StandardWrapperValve.invoke (StandardWrapperValve.java:213) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178) at org.apache.geronimo.tomcat.valve.DefaultSubjectValve.invoke (DefaultSubjectValve.java:46) at org.apache.geronimo.tomcat.GeronimoStandardContext$SystemMethodValve.invoke(GeronimoStandardContext.java:342) at org.apache.geronimo.tomcat.valve.GeronimoBeforeAfterValve.invoke(GeronimoBeforeAfterValve.java:31) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105) at org.apache.catalina.core.StandardEngineValve.invoke (StandardEngineValve.java:107) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541) at org.apache.catalina.authenticator.SingleSignOn.invoke(SingleSignOn.java:392) at org.apache.catalina.connector.CoyoteAdapter.service (CoyoteAdapter.java:148) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869) at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java :667) at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527) at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run (ThreadPool.java:869) at java.lang.Thread.run(Thread.java:799) It looks to me as if UsersMetaClass.newObject(ctx) should return an instance of UsersClass (this is what StringMetaClass does for example). It also looks like GroupMetaClass does the same.... Incidently, is there a way to remove an unwanted property from the class ? During my experiment I added a DBListClass (to test this) but can't see how to remove it. Cheers, Dan PS. Top job on getting b2 out :)