NPE when doing hasParentFilter with a nestedFilter

gistfile1.txt

[2014-01-28 23:08:50,080][DEBUG][action.search.type       ] [Double Helix] [3] Failed to execute fetch phase
java.lang.NullPointerException
	at org.elasticsearch.index.search.child.ParentConstantScoreQuery$ChildrenWeight$ChildrenDocIdIterator.match(ParentConstantScoreQuery.java:176)
	at org.apache.lucene.search.FilteredDocIdSetIterator.advance(FilteredDocIdSetIterator.java:71)
	at org.elasticsearch.index.search.child.ConstantScorer.advance(ConstantScorer.java:70)
	at org.apache.lucene.search.ConstantScoreQuery$ConstantScorer.advance(ConstantScoreQuery.java:217)
	at org.apache.lucene.search.ConstantScoreQuery$ConstantWeight.explain(ConstantScoreQuery.java:166)
	at org.apache.lucene.search.FilteredQuery$1.explain(FilteredQuery.java:102)
	at org.apache.lucene.search.IndexSearcher.explain(IndexSearcher.java:672)
	at org.apache.lucene.search.IndexSearcher.explain(IndexSearcher.java:652)
	at org.elasticsearch.search.internal.ContextIndexSearcher.explain(ContextIndexSearcher.java:192)
	at org.elasticsearch.search.fetch.explain.ExplainFetchSubPhase.hitExecute(ExplainFetchSubPhase.java:72)
	at org.elasticsearch.search.fetch.FetchPhase.execute(FetchPhase.java:197)
	at org.elasticsearch.search.SearchService.executeFetchPhase(SearchService.java:434)
	at org.elasticsearch.search.action.SearchServiceTransportAction.sendExecuteFetch(SearchServiceTransportAction.java:406)
	at org.elasticsearch.action.search.type.TransportSearchDfsQueryThenFetchAction$AsyncAction.executeFetch(TransportSearchDfsQueryThenFetchAction.java:249)
	at org.elasticsearch.action.search.type.TransportSearchDfsQueryThenFetchAction$AsyncAction$5.run(TransportSearchDfsQueryThenFetchAction.java:233)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:744)

gistfile2.json

{
    "template_products": {
        "template": "products*",
        "mappings": {
            "products": {
                "_all": {
                    "enabled": false
                },
                "_source": {
                    "compress": true
                },
                "properties": {
                    "_id": {
                        "index": "not_analyzed",
                        "type": "string"
                    },
                    "items": {
                        "type": "nested",
                        "include_in_parent": true,
                        "properties": {
                             "itemId": {
                                "index": "not_analyzed",
                                "type": "string"
                            },
                            "companyId": {
                                "type": "long"
                            }
                        }
                    }
                }
            },
            "items": {
                "_all": {
                    "enabled": false
                },
                "_parent": {
                    "type": "products"
                },
                "_routing": {
                    "required": true,
                    "path": "productId"
                },
                "_source": {
                    "compress": true
                },
                "properties": {
                    "_id": {
                        "index": "not_analyzed",
                        "type": "string"
                    },
                    "description": {
                        "type": "string"
                    },
                    "productId": {
                        "index": "not_analyzed",
                        "type": "string"
                    }
                }
            }
        }
    }
}

gistfile3.java

BoolFilterBuilder boolFilter = FilterBuilders.boolFilter();
boolFilter.must(FilterBuilders.termFilter("items.itemId", itemId));
boolFilter.must(FilterBuilders.termFilter("items.companyId", session.getCompanyId()));
NestedFilterBuilder crossCompanyFilter = FilterBuilders.nestedFilter("items", boolFilter);

FilteredQueryBuilder fqb = QueryBuilders.filteredQuery(QueryBuilders.matchAllQuery(), FilterBuilders.hasParentFilter("products", crossCompanyFilter));