org.jboss.cache.optimistic.DataVersioningException for jBPM entities in SOA-P 5

Issue

We are using a clustered server profile where jBPM is set up to use JBoss Cache as 2nd level cache provider:

    <!-- Clustered cache (begin) -->
    <property name="hibernate.cache.provider_class">
      org.jboss.hibernate.jbc.cacheprovider.JmxBoundTreeCacheProvider
    </property>
    <property name="hibernate.treecache.mbean.object_name">jboss.jbpm:service=TreeCache</property>

    <property name="hibernate.cache.region.factory_class">
      org.hibernate.cache.jbc2.JndiMultiplexedJBossCacheRegionFactory
    </property>
    <property name="hibernate.cache.region.jbc2.cachefactory">java:CacheManager</property>
    <property name="hibernate.cache.region_prefix">jbpm3</property>
    <!-- Clustered cache (end) -->

But sometimes we are getting below warning message from cache class:

WARN  [org.jboss.cache.interceptors.OptimisticTxInterceptor] (pool-90-thread-3) Caught exception, will now set transaction to roll back
org.jboss.cache.optimistic.DataVersioningException: Transaction attempted to create /org/jbpm/graph/def/Node/ENTITY/org.jbpm.graph.def.Node#9812 anew.
It has already been created since this transaction started, by another (possibly remote) transaction.  We have a concurrent creation event.
     at org.jboss.cache.interceptors.OptimisticValidatorInterceptor.visitOptimisticPrepareCommand(OptimisticValidatorInterceptor.java:116)
     at org.jboss.cache.commands.tx.OptimisticPrepareCommand.acceptVisitor(OptimisticPrepareCommand.java:55)
     at org.jboss.cache.interceptors.base.CommandInterceptor.invokeNextInterceptor(CommandInterceptor.java:116)
     at org.jboss.cache.interceptors.OptimisticLockingInterceptor.visitOptimisticPrepareCommand(OptimisticLockingInterceptor.java:89)