As of JDK 7 b37.
The JSR 262 TCK test that failed is api/javax_management/remote/protocol/WsMBeanServerNotification2Test.html#WsMBeanServerNotification2Test
The failure occurred at the very end of the ProtocolTest0001 test case, during its cleaning sequence.
That failure occurs for the first time and doesn't occur at each run.
TCK code does (line 616 of RjmxDistributedTest):
    client.removeNotificationListener(name, listener);

The stack is:

stopTest1
send jmxCheckerDown
send jmxServerDown
java.io.IOException: Ended!
at javax.management.event.EventClient.checkState(EventClient.java:845)
at javax.management.event.EventClient.removeNotificationListener(EventClient.java:421)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:623)
at com.sun.jmx.remote.ws.DependencyChecker.invoke(DependencyChecker.java:85)
at com.sun.jmx.remote.ws.EventServiceFactory.invokeOnTarget(EventServiceFactory.java:430)
at com.sun.jmx.remote.ws.EventServiceFactory.access$100(EventServiceFactory.java:41)
at com.sun.jmx.remote.ws.EventServiceFactory$EventClientBridge.invoke(EventServiceFactory.java:454)
at $Proxy172.removeNotificationListener(Unknown Source)
at com.sun.jmx.remote.ws.client.JMXWSConnector$RemoteMBeanServerConnection.invoke(JMXWSConnector.java:217)
at $Proxy170.removeNotificationListener(Unknown Source)
at javasoft.sqe.tests.api.javax.management.remote.utils.RjmxDistributedTest.do_jmxClientRemoveNotificationListener(RjmxDistributedTest.java:616)
at javasoft.sqe.tests.api.javax.management.remote.protocol.ProtocolMBeanServerNotification2Test.ProtocolTest0001(ProtocolMBeanServerNotification2Test.java:221)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:623)
at javasoft.sqe.javatest.lib.TestCases.invokeTestCases(TestCases.java:173)
at javasoft.sqe.tests.api.javax.management.remote.utils.DistributedMultiTest.go(DistributedMultiTest.java:62)
at javasoft.sqe.tests.api.javax.management.remote.utils.RjmxDistributedMultiTest.go(RjmxDistributedMultiTest.java:121)
at com.sun.tck.lib.DistributedTest.run(DistributedTest.java:71)
at javasoft.sqe.tests.api.javax.management.remote.utils.DistributedMultiTest.run(DistributedMultiTest.java:40)
at javasoft.sqe.tests.api.javax.management.remote.utils.RjmxDistributedMultiTest.run(RjmxDistributedMultiTest.java:73)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:623)
at com.sun.tck.lib.ExecTCKTestSameJVMCmd$Version2Test.execute(ExecTCKTestSameJVMCmd.java:483)
at com.sun.tck.lib.ExecTCKTestSameJVMCmd$StandardTest.run(ExecTCKTestSameJVMCmd.java:395)
at com.sun.tck.lib.ExecTCKTestSameJVMCmd.execute(ExecTCKTestSameJVMCmd.java:263)
at com.sun.tck.lib.ExecTCKTestSameJVMCmd.run(ExecTCKTestSameJVMCmd.java:169)
at com.sun.javatest.agent.Agent$Task.executeCommand(Agent.java:841)
at com.sun.javatest.agent.Agent$Task.execute(Agent.java:772)
at com.sun.javatest.agent.Agent$Task.handleRequest(Agent.java:633)
at com.sun.javatest.agent.Agent.handleRequestsUntilClosed(Agent.java:400)
at com.sun.javatest.agent.Agent.access$000(Agent.java:60)
at com.sun.javatest.agent.Agent$1.run(Agent.java:272)
at java.lang.Thread.run(Thread.java:713)