kryo serialization problem

Performing a cross of two dataset of POJOs I have got the exception below. The first time I run the process, there was no problem. When I run it the second time, I have got the exception. My guess is that it could be a race condition related to the reuse of the Kryo serializer object. However, it could also be "a bug where type registrations are not properly forwarded to all Serializers", as suggested by Stephan.

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2015-10-01 18:18:21 INFO JobClient:161 - 10/01/2015 18:18:21 Cross(Cross at main(FlinkMongoHadoop2LinkPOI2CDA.java:160))(3/4) switched to FAILED
com.esotericsoftware.kryo.KryoException: Encountered unregistered class ID: 114
at com.esotericsoftware.kryo.util.DefaultClassResolver.readClass(DefaultClassResolver.java:119)
at com.esotericsoftware.kryo.Kryo.readClass(Kryo.java:641)
at com.esotericsoftware.kryo.Kryo.readClassAndObject(Kryo.java:752)
at org.apache.flink.api.java.typeutils.runtime.kryo.KryoSerializer.deserialize(KryoSerializer.java:210)
at org.apache.flink.api.java.typeutils.runtime.TupleSerializer.deserialize(TupleSerializer.java:127)
at org.apache.flink.api.java.typeutils.runtime.TupleSerializer.deserialize(TupleSerializer.java:30)
at org.apache.flink.runtime.operators.resettable.AbstractBlockResettableIterator.getNextRecord(AbstractBlockResettableIterator.java:180)
at org.apache.flink.runtime.operators.resettable.BlockResettableMutableObjectIterator.next(BlockResettableMutableObjectIterator.java:111)
at org.apache.flink.runtime.operators.CrossDriver.runBlockedOuterSecond(CrossDriver.java:309)
at org.apache.flink.runtime.operators.CrossDriver.run(CrossDriver.java:162)
at org.apache.flink.runtime.operators.RegularPactTask.run(RegularPactTask.java:489)
at org.apache.flink.runtime.operators.RegularPactTask.invoke(RegularPactTask.java:354)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:581)
at java.lang.Thread.run(Thread.java:745)