Neo4j 2.3.0 changed the format of the neostore.nodestore.db
This causes Neo4j databases created w/ Gremlin-server (e.g. /tmp/neo4j) and neo4j databases created by the neo4j server from neo4j.com to be incompatible with each other. Also Gremlin-server/console cannot open databases created by the newer Neo4j code.
pull request is here (it passed all tests w/ "mvn clean install" )