Vaadin 7 + GAE (Managed VMs) AtmosphereFramework exception

Hi,

I using vaadin 7.3.5 on a Google App Engine (Managed VMs)
https://cloud.google.com/appengine/docs/java/managed-vms/

server is starting:

/PUSH/?v-uiId=15&v-csrfToken=a02ea6ff-7f6f-4413-8710-8bb7afd3becb&X-Atmosphere-tracking-id=35bd99f5-250e-43dc-b358-ab70f60fb747&X-Atmosphere-Framework=2.1.5.vaadin4-jquery&X-Atmosphere-Transport=long-polling&X-Atmosphere-TrackMessageSize=true&X-Cache-Date=0&Content-Type=application%2Fjson%3B%20charset%3DUTF-8&X-atmo-protocol=true&_=1416690704263 200 1180ms 2kb instance=0 Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.65 Safari/537.36 module=default version=xxxx
49.230.83.154 - - [22/Nov/2014:13:11:44 -0800]
 "GET /PUSH/?v-uiId=15&v-csrfToken=a02ea6ff-7f6f-4413-8710-8bb7afd3becb&X-Atmosphere-tracking-id=35bd99f5-250e-43dc-b358-ab70f60fb747&X-Atmosphere-Framework=2.1.5.vaadin4-jquery&X-Atmosphere-Transport=long-polling&X-Atmosphere-TrackMessageSize=true&X-Cache-Date=0&Content-Type=application%2Fjson%3B%20charset%3DUTF-8&X-atmo-protocol=true&_=1416690704263 HTTP/1.1" 200 2626 "http://xxxx.appspot.com/" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.65 Safari/537.36" "xxxx.appspot.com" ms=1180 cpu_ms=0 cpm_usd=0.000293 instance=0 app_engine_release=1.9.16 
E 2014-11-23 04:11:43.302
org.atmosphere.cpr.AtmosphereFramework doCometSupport: AtmosphereFramework exception
java.lang.IllegalStateException: !asyncSupported
    at org.eclipse.jetty.server.Request.startAsync(Request.java:2074)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:384)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:384)
    at org.atmosphere.cpr.AtmosphereRequest.startAsync(AtmosphereRequest.java:678)
    at org.atmosphere.container.Servlet30CometSupport.suspend(Servlet30CometSupport.java:93)
    at org.atmosphere.container.Servlet30CometSupport.service(Servlet30CometSupport.java:68)
    at org.atmosphere.container.JettyServlet30AsyncSupportWithWebSocket.service(JettyServlet30AsyncSupportWithWebSocket.java:53)
    at org.atmosphere.cpr.AtmosphereFramework.doCometSupport(AtmosphereFramework.java:1802)
    at com.vaadin.server.communication.PushRequestHandler.handleRequest(PushRequestHandler.java:144)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1406)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:305)
    at com.vaadin.server.GAEVaadinServlet.service(GAEVaadinServlet.java:254)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:769)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1667)
    at com.google.apphosting.utils.servlet.ParseBlobUploadFilter.doFilter(ParseBlobUploadFilter.java:125)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at com.google.apphosting.runtime.jetty9.SaveSessionFilter.doFilter(SaveSessionFilter.java:35)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:583)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:553)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1125)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1059)
    at com.google.apphosting.vmruntime.jetty9.VmRuntimeWebAppContext.doScope(VmRuntimeWebAppContext.java:412)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
    at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:497)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:248)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:610)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:539)
    at java.lang.Thread.run(Thread.java:745)
E 2014-11-23 04:11:43.305
com.vaadin.server.DefaultErrorHandler doDefault: 
java.lang.IllegalStateException: !asyncSupported
    at org.eclipse.jetty.server.Request.startAsync(Request.java:2074)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:384)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:384)
    at org.atmosphere.cpr.AtmosphereRequest.startAsync(AtmosphereRequest.java:678)
    at org.atmosphere.container.Servlet30CometSupport.suspend(Servlet30CometSupport.java:93)
    at org.atmosphere.container.Servlet30CometSupport.service(Servlet30CometSupport.java:68)
    at org.atmosphere.container.JettyServlet30AsyncSupportWithWebSocket.service(JettyServlet30AsyncSupportWithWebSocket.java:53)
    at org.atmosphere.cpr.AtmosphereFramework.doCometSupport(AtmosphereFramework.java:1802)
    at com.vaadin.server.communication.PushRequestHandler.handleRequest(PushRequestHandler.java:144)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1406)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:305)
    at com.vaadin.server.GAEVaadinServlet.service(GAEVaadinServlet.java:254)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:769)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1667)
    at com.google.apphosting.utils.servlet.ParseBlobUploadFilter.doFilter(ParseBlobUploadFilter.java:125)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at com.google.apphosting.runtime.jetty9.SaveSessionFilter.doFilter(SaveSessionFilter.java:35)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:583)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:553)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1125)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1059)
    at com.google.apphosting.vmruntime.jetty9.VmRuntimeWebAppContext.doScope(VmRuntimeWebAppContext.java:412)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
    at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:497)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:248)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:610)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:539)
    at java.lang.Thread.run(Thread.java:745)
W 2014-11-23 04:11:43.312
com.vaadin.server.GAEVaadinServlet service: An exception occurred while servicing request.
javax.servlet.ServletException: com.vaadin.server.ServiceException: java.lang.IllegalStateException: !asyncSupported
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:307)
    at com.vaadin.server.GAEVaadinServlet.service(GAEVaadinServlet.java:254)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:769)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1667)
    at com.google.apphosting.utils.servlet.ParseBlobUploadFilter.doFilter(ParseBlobUploadFilter.java:125)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at com.google.apphosting.runtime.jetty9.SaveSessionFilter.doFilter(SaveSessionFilter.java:35)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:583)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:553)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1125)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1059)
    at com.google.apphosting.vmruntime.jetty9.VmRuntimeWebAppContext.doScope(VmRuntimeWebAppContext.java:412)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
    at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:497)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:248)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:610)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:539)
    at java.lang.Thread.run(Thread.java:745)
Caused by: com.vaadin.server.ServiceException: java.lang.IllegalStateException: !asyncSupported
    at com.vaadin.server.VaadinService.handleExceptionDuringRequest(VaadinService.java:1464)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1418)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:305)
    ... 30 more
Caused by: java.lang.IllegalStateException: !asyncSupported
    at org.eclipse.jetty.server.Request.startAsync(Request.java:2074)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:384)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:384)
    at org.atmosphere.cpr.AtmosphereRequest.startAsync(AtmosphereRequest.java:678)
    at org.atmosphere.container.Servlet30CometSupport.suspend(Servlet30CometSupport.java:93)
    at org.atmosphere.container.Servlet30CometSupport.service(Servlet30CometSupport.java:68)
    at org.atmosphere.container.JettyServlet30AsyncSupportWithWebSocket.service(JettyServlet30AsyncSupportWithWebSocket.java:53)
    at org.atmosphere.cpr.AtmosphereFramework.doCometSupport(AtmosphereFramework.java:1802)
    at com.vaadin.server.communication.PushRequestHandler.handleRequest(PushRequestHandler.java:144)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1406)
    ... 31 more

User action:

"GET /_ah/background HTTP/1.1" 200 0 - - "0.xxxx.appspot.com" ms=3540712 cpu_ms=0 instance=0 app_engine_release=1.9.16 
W 2014-11-23 04:01:11.260
com.google.apphosting.vmruntime.jetty9.VmRuntimeWebAppContext handleLocalHealthCheck: unhealthy (isLastSuccessful is False)
W 2014-11-23 04:01:13.719
com.google.apphosting.vmruntime.jetty9.VmRuntimeWebAppContext handleLocalHealthCheck: unhealthy (isLastSuccessful is False)
W 2014-11-23 04:01:15.741
com.google.apphosting.vmruntime.jetty9.VmRuntimeWebAppContext handleLocalHealthCheck: unhealthy (isLastSuccessful is False)
W 2014-11-23 04:01:17.854
org.atmosphere.cpr.DefaultAnnotationProcessor fallbackToManualAnnotatedClasses: Unable to detect annotations. Application may fail to deploy.
E 2014-11-23 04:11:44.345
com.vaadin.server.communication.PushHandler disconnect: Session expired before push was disconnected. This should never happen
com.vaadin.server.SessionExpiredException
    at com.vaadin.server.VaadinService.doFindOrCreateVaadinSession(VaadinService.java:728)
    at com.vaadin.server.VaadinService.findOrCreateVaadinSession(VaadinService.java:663)
    at com.vaadin.server.VaadinService.findVaadinSession(VaadinService.java:522)
    at com.vaadin.server.communication.PushHandler.disconnect(PushHandler.java:351)
    at com.vaadin.server.communication.PushHandler.onDisconnect(PushHandler.java:330)
    at org.atmosphere.cpr.AtmosphereResourceImpl.onDisconnect(AtmosphereResourceImpl.java:663)
    at org.atmosphere.cpr.AtmosphereResourceImpl.notifyListeners(AtmosphereResourceImpl.java:582)
    at org.atmosphere.cpr.AtmosphereResponse.handleException(AtmosphereResponse.java:871)
    at org.atmosphere.cpr.AtmosphereResponse.write(AtmosphereResponse.java:968)
    at org.atmosphere.cpr.AtmosphereResponse.write(AtmosphereResponse.java:934)
    at org.atmosphere.cpr.AtmosphereInterceptorWriter.writeReady(AtmosphereInterceptorWriter.java:89)
    at org.atmosphere.cpr.AtmosphereInterceptorWriter.invokeInterceptor(AtmosphereInterceptorWriter.java:78)
    at org.atmosphere.cpr.AtmosphereInterceptorWriter.write(AtmosphereInterceptorWriter.java:64)
    at org.atmosphere.cpr.AtmosphereInterceptorWriter.write(AtmosphereInterceptorWriter.java:59)
    at org.atmosphere.cpr.AtmosphereResponse$2.write(AtmosphereResponse.java:503)
    at org.atmosphere.handler.AbstractReflectorAtmosphereHandler.onStateChange(AbstractReflectorAtmosphereHandler.java:141)
    at com.vaadin.server.communication.PushHandler$1.onStateChange(PushHandler.java:63)
    at org.atmosphere.cpr.DefaultBroadcaster.invokeOnStateChange(DefaultBroadcaster.java:1018)
    at org.atmosphere.cpr.DefaultBroadcaster.prepareInvokeOnStateChange(DefaultBroadcaster.java:1038)
    at org.atmosphere.cpr.DefaultBroadcaster.executeAsyncWrite(DefaultBroadcaster.java:879)
    at org.atmosphere.cpr.DefaultBroadcaster$3.run(DefaultBroadcaster.java:520)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    at java.util.concurrent.FutureTask.run(FutureTask.java:262)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)