See the topic on the forum :
http://forum.hibernate.org/viewtopic.php?t=969417
I've reproduced a unit test that shows the problem.
It's the "testQueryCacheInvalidationVersionedItem()" test method in the "org.hibernate.test.cache.BaseCacheProviderTestCase" class.
This looks like it's related to/probably fixed by http://jira.jboss.com/jira/browse/JBCACHE-953
.