Session already invalidated error on requestDestroyed callback

We use the org.jboss.weld.environment.servlet.Listener to enable our servlet application to use weld.
On user logout we invalidate the session and redirect the user away.
It seems like tomcat is firing a requestDestroyed when we do that (that is, after we invalidate the session)

The weld code then produces this stack trace:

java.lang.IllegalStateException: getAttribute: Session already invalidated
at org.apache.catalina.session.StandardSession.getAttribute(StandardSession.java:1167)
at org.apache.catalina.session.StandardSessionFacade.getAttribute(StandardSessionFacade.java:122)
at org.jboss.weld.context.http.HttpConversationContextImpl.getSessionAttribute(HttpConversationContextImpl.java:29)
at org.jboss.weld.context.http.HttpConversationContextImpl.getSessionAttribute(HttpConversationContextImpl.java:13)
at org.jboss.weld.context.AbstractConversationContext.copyConversationIdGeneratorAndConversationsToSession(AbstractConversationContext.java:177)
at org.jboss.weld.context.AbstractConversationContext.dissociate(AbstractConversationContext.java:161)
at org.jboss.weld.servlet.ConversationContextActivator.disassociateConversationContext(ConversationContextActivator.java:171)
at org.jboss.weld.servlet.HttpContextLifecycle.requestDestroyed(HttpContextLifecycle.java:236)
at org.jboss.weld.servlet.WeldInitialListener.requestDestroyed(WeldInitialListener.java:118)
at org.jboss.weld.servlet.api.helpers.ForwardingServletListener.requestDestroyed(ForwardingServletListener.java:38)
at org.apache.catalina.core.StandardContext.fireRequestDestroyEvent(StandardContext.java:6137)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:207)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
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:744)

I feel that somehow copyConversationIdGeneratorAndConversationsToSession should check if the session is valid.
On the other hand, I wonder if that conversation context dance need to be done at all. We are not using this scope.