java.io.FileNotFoundException in JCR with EPP 5

Issue

• We deleted ${gatein.jcr.data.dir} and start the server to rebuild the jcr index. No error is reported during server start up. But when we access the portal, more precisely, when we access a gadget, we run into a FileNotFoundException:

  Caused by: java.io.FileNotFoundException: 
                   /app/portal/gatein/jcr/values/portal-system/9/a/c/3/b/b/4/9ac3bb480a0dae3f73fea1eef0fcd8a00
                   (No such file or directory)
  

${gatein.data.dir} is pointing to a nfs file system, as defined in $JBOSS_HOME/jboss-as/server/$CONFIG/conf/gatein/configuration.properties:

# Data
gatein.data.dir=/app/portal/gatein

# DB
gatein.db.data.dir=${gatein.data.dir}/db

# JCR
gatein.jcr.config.type=cluster
gatein.jcr.datasource.name=java:gatein-jcr
gatein.jcr.datasource.dialect=auto

gatein.jcr.data.dir=${gatein.data.dir}/jcr
gatein.jcr.storage.data.dir=${gatein.jcr.data.dir}/values
gatein.jcr.index.data.dir=${gatein.jcr.data.dir}/lucene
gatein.jcr.index.changefilterclass=org.exoplatform.services.jcr.impl.core.query.jbosscache.JBossCacheIndexChangesFilter

Our portal data source is pointing to Oracle.  How can we recover this? Is is going to help if we drop all tables and let portal to rebuild very thing?