Hi, all! I need to use documents grouping, but my db is sharded.

I try use mapreduce:

Code:
MapReduceResults<ValueObject> results =  mongoOperations.mapReduce(query, table, functionMap, functionReduce, ValueObject.class);
But I get exception:

Code:
java.lang.Long cannot be cast to java.lang.Integer
java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Integer
	at org.springframework.data.mongodb.core.mapreduce.MapReduceResults.parseCounts(MapReduceResults.java:125) ~[spring-data-mongodb-1.1.0.RELEASE.jar:na]
	at org.springframework.data.mongodb.core.mapreduce.MapReduceResults.<init>(MapReduceResults.java:54) ~[spring-data-mongodb-1.1.0.RELEASE.jar:na]
	at org.springframework.data.mongodb.core.MongoTemplate.mapReduce(MongoTemplate.java:1105) ~[spring-data-mongodb-1.1.0.RELEASE.jar:na]
	at org.springframework.data.mongodb.core.MongoTemplate.mapReduce(MongoTemplate.java:1071) ~[spring-data-mongodb-1.1.0.RELEASE.jar:na]
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