Wildfly 8.2 : session attributes disapear, when using mod cluster

Question

we're using wildfly 8.2 in cluster mode , with ha profil, so as to benefit from failover fonctionnality.

But seems that things don't work properly since we enable </distributable> in our web.xml, because session attributes disapear from user's session abnormally.

Here is our cache configuration in domain.xml:

    <cache-container name="web" default-cache="dist" module="org.wildfly.clustering.web.infinispan">
                        <transport lock-timeout="60000"/>
                        <local-cache name="passivation" batching="true">
                            <file-store passivation="true" purge="false"/>
                        </local-cache>
                        <distributed-cache name="dist" batching="true" mode="ASYNC" owners="2" l1-lifespan="0">
                            <locking isolation="READ_COMMITTED" striping="false" acquire-timeout="30000" concurrency-level="20000"/>
                            <transaction locking="OPTIMISTIC"/>
                            <file-store/>
                        </distributed-cache>
  </cache-container>

Is someone facing the same problem? is this problem caused by session passivation ?