Just upgraded from 4.0d and I am getting following randomly or probably on every page i browse in share
SEVERE: Incorrect ACL set269675 CacheEntry [dbid=89986, leaf=0, path=269675, aclid=0, owner=0]
java.lang.IllegalStateException: Cache position check failed
at org.alfresco.solr.AlfrescoSolrEventListener$AbstractCacheMatch.checkCachePosition(AlfrescoSolrEventListener.java:1899)
at org.alfresco.solr.AlfrescoSolrEventListener$Match.updateCache(AlfrescoSolrEventListener.java:2553)
at org.alfresco.solr.AlfrescoSolrEventListener.newSearcher(AlfrescoSolrEventListener.java:332)
at org.apache.solr.core.SolrCore$4.call(SolrCore.java:1163)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)
I am not using solr but lucene if that helps.