Possible NPE when reindexing node-type indexes

modeshape-reindexing-4-thread-1 11:32:04,455 ERROR Error while indexing '/' in workspace 'default': null
java.lang.NullPointerException
	at java.util.concurrent.ConcurrentHashMap.hash(ConcurrentHashMap.java:333)
	at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:988)
	at org.modeshape.jcr.cache.document.LazyCachedNode$1.getProperty(LazyCachedNode.java:413)
	at org.modeshape.jcr.index.local.IndexChangeAdapters$AbstractPropertyChangeAdapter.reindexNode(IndexChangeAdapters.java:487)
	at org.modeshape.jcr.spi.index.provider.IndexChangeAdapter.index(IndexChangeAdapter.java:66)
	at org.modeshape.jcr.spi.index.provider.IndexProvider$7.add(IndexProvider.java:802)
	at org.modeshape.jcr.spi.index.provider.IndexProvider$1.add(IndexProvider.java:190)
	at org.modeshape.jcr.RepositoryQueryManager.reindexContent(RepositoryQueryManager.java:435)
	at org.modeshape.jcr.RepositoryQueryManager$2$1.scan(RepositoryQueryManager.java:282)
	at org.modeshape.jcr.RepositoryIndexManager$ScanningRequest.onEachPathInWorkspace(RepositoryIndexManager.java:889)
	at org.modeshape.jcr.RepositoryQueryManager$2.call(RepositoryQueryManager.java:288)
	at org.modeshape.jcr.RepositoryQueryManager$2.call(RepositoryQueryManager.java:255)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:724)