Hazelcast 2.6.4: ZipException: unknown compression method

[maro]

In a test with an 8 member cluster we get a lot of the following exceptions in all members of the cluster:

2014-01-29 22:54:56,459 [host:S21SLJBS04] WARN  com.hazelcast.impl.partition.MigrationTask [Thread:hz._hzInstance_1_SecDocsCentricStore.cached.thread-22]: [172.17.71.250]:5701 [SecDocsCentricStore] unknown compression method
java.util.zip.ZipException: unknown compression method
    at java.util.zip.InflaterInputStream.read(InflaterInputStream.java:147)
    at java.util.zip.InflaterInputStream.read(InflaterInputStream.java:105)
    at java.io.DataInputStream.readInt(DataInputStream.java:370)
    at com.hazelcast.impl.partition.MigrationTask.call(MigrationTask.java:89)
    at com.hazelcast.impl.partition.MigrationTask.call(MigrationTask.java:40)
    at com.hazelcast.impl.ExecutorManager$RequestExecutor.run(ExecutorManager.java:281)
    at com.hazelcast.impl.executor.ParallelExecutorService$ParallelExecutorImpl$ExecutionSegment.run(ParallelExecutorService.java:230)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
    at java.lang.Thread.run(Thread.java:662)
    at com.hazelcast.impl.ExecutorThreadFactory$1.run(ExecutorThreadFactory.java:45)

What is the reason for such an exception?

Best,
Manfred