ClassCastException in com.atlassian.xwork12.Xwork12VersionSupport.extractAction

From a customer log:

09:50:36 ERROR - /json/fe/globalQuicksearch-ajax.do
java.lang.ClassCastException: com.atlassian.fisheye.quicksearch.action.CrossRepositoryQuickSearchAjaxAction cannot be cast to com.opensymphony.xwork.Action
at com.atlassian.xwork12.Xwork12VersionSupport.extractAction(Xwork12VersionSupport.java:14)
at com.atlassian.xwork.interceptors.SafeParametersInterceptor.shouldNotIntercept(SafeParametersInterceptor.java:88)
at com.atlassian.xwork.interceptors.SafeParametersInterceptor.before(SafeParametersInterceptor.java:94)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:30)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.webwork.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:174)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.webwork.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:169)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:151)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:186)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:116)
at com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:273)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:502)
at org.mortbay.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1208)
at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:55)
at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:41)
at org.mortbay.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1200)
at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:55)
at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:41)
at org.mortbay.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1200)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:83)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.mortbay.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1200)
at com.cenqua.crucible.filters.CrucibleFilter.doFilter(CrucibleFilter.java:141)