Some tests fail when building on a Windows box

Trying to create a ZIP distro from sources failed.
On Win7. On cygwin, command shell and git bash.
Tried with incubator-src download from ASF download page, as well as fresh checkout from latest trunk (r1329547).
Once I tried the same on a Linux box, everything was working ok.

svn co http://svn.apache.org/repos/asf/incubator/kafka/trunk kafka-0.7.0
./sbt update (OK)
./sbt package (OK)
./sbt release-zip (FAIL)
Tests failing:
[error] Error running kafka.integration.LazyInitProducerTest: Test FAILED
[error] Error running kafka.zk.ZKLoadBalanceTest: Test FAILED
[error] Error running kafka.javaapi.producer.ProducerTest: Test FAILED
[error] Error running kafka.producer.ProducerTest: Test FAILED
[error] Error running test: One or more subtasks failed
[error] Error running doc: Scaladoc generation failed
Stacks:
[error] Test Failed: testZKSendWithDeadBroker
junit.framework.AssertionFailedError: Message set should have another message
at junit.framework.Assert.fail(Assert.java:47)
at junit.framework.Assert.assertTrue(Assert.java:20)
at kafka.javaapi.producer.ProducerTest.testZKSendWithDeadBroker(ProducerTest.scala:448)
[error] Test Failed: testZKSendToNewTopic
junit.framework.AssertionFailedError: Message set should have 1 message
at junit.framework.Assert.fail(Assert.java:47)
at junit.framework.Assert.assertTrue(Assert.java:20)
at kafka.javaapi.producer.ProducerTest.testZKSendToNewTopic(ProducerTest.scala:416)
[error] Test Failed: testLoadBalance(kafka.zk.ZKLoadBalanceTest)
junit.framework.AssertionFailedError: expected:<5> but was:<0>
at junit.framework.Assert.fail(Assert.java:47)
at junit.framework.Assert.failNotEquals(Assert.java:277)
at junit.framework.Assert.assertEquals(Assert.java:64)
at junit.framework.Assert.assertEquals(Assert.java:195)
at junit.framework.Assert.assertEquals(Assert.java:201)
at kafka.zk.ZKLoadBalanceTest.checkSetEqual(ZKLoadBalanceTest.scala:121)
at kafka.zk.ZKLoadBalanceTest.testLoadBalance(ZKLoadBalanceTest.scala:89)
[error] Test Failed: testPartitionedSendToNewTopic
java.lang.AssertionError:
Unexpected method call send("test-topic1", 0, ByteBufferMessageSet(MessageAndOffset(message(magic = 1, attributes = 0, crc = 2326977762, payload = java.nio.HeapByteBuffer[pos=0 lim=5 cap=5]),15), )):
close(): expected: 1, actual: 0
at org.easymock.internal.MockInvocationHandler.invoke(MockInvocationHandler.java:45)
at org.easymock.internal.ObjectMethodsFilter.invoke(ObjectMethodsFilter.java:73)
at org.easymock.internal.ClassProxyFactory$MockMethodInterceptor.intercept(ClassProxyFactory.java:92)
at kafka.producer.SyncProducer$$EnhancerByCGLIB$$4385e618.send(<generated>)
at kafka.producer.ProducerPool$$anonfun$send$1.apply$mcVI$sp(ProducerPool.scala:114)
at kafka.producer.ProducerPool$$anonfun$send$1.apply(ProducerPool.scala:100)
at kafka.producer.ProducerPool$$anonfun$send$1.apply(ProducerPool.scala:100)
at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:57)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:43)
at kafka.producer.ProducerPool.send(ProducerPool.scala:100)
at kafka.producer.Producer.zkSend(Producer.scala:137)
at kafka.producer.Producer.send(Producer.scala:99)
at kafka.producer.ProducerTest.testPartitionedSendToNewTopic(ProducerTest.scala:576)
[error] Test Failed: testZKSendToNewTopic
junit.framework.AssertionFailedError: Message set should have 1 message
at junit.framework.Assert.fail(Assert.java:47)
at junit.framework.Assert.assertTrue(Assert.java:20)
at kafka.producer.ProducerTest.testZKSendToNewTopic(ProducerTest.scala:429)