IIOP serialization fails with NullPointerException when serializing Throwable

The following tests are currently failing in the TL forest (currenly at jdk7-b139 + changes for b140 and b142).

javax/management/remote/mandatory/loading/MethodResultTest.java
javax/management/remote/mandatory/serverError/JMXServerErrorTest.java

The tests are failing with a NullPointerException with stack traces such as the following:

java.lang.NullPointerException
at java.util.Hashtable.put(Hashtable.java:432)
at com.sun.corba.se.impl.io.OutputStreamHook$HookPutFields.put(OutputStreamHook.java:115)
at java.lang.Throwable.writeObject(Throwable.java:963)
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:601)
at com.sun.corba.se.impl.io.IIOPOutputStream.invokeObjectWriter(IIOPOutputStream.java:620)
at com.sun.corba.se.impl.io.IIOPOutputStream.outputObject(IIOPOutputStream.java:586)
at com.sun.corba.se.impl.io.IIOPOutputStream.simpleWriteObject(IIOPOutputStream.java:174)
at com.sun.corba.se.impl.io.ValueHandlerImpl.writeValueInternal(ValueHandlerImpl.java:228)
at com.sun.corba.se.impl.io.ValueHandlerImpl.writeValueWithVersion(ValueHandlerImpl.java:210)
at com.sun.corba.se.impl.io.ValueHandlerImpl.writeValue(ValueHandlerImpl.java:150)
at com.sun.corba.se.impl.encoding.CDROutputStream_1_0.writeRMIIIOPValueType(CDROutputStream_1_0.java:817)
at com.sun.corba.se.impl.encoding.CDROutputStream_1_0.write_value(CDROutputStream_1_0.java:866)
at com.sun.corba.se.impl.encoding.CDROutputStream_1_0.write_value(CDROutputStream_1_0.java:880)
at com.sun.corba.se.impl.encoding.CDROutputStream.write_value(CDROutputStream.java:246)
at com.sun.corba.se.spi.servicecontext.UEInfoServiceContext.writeData(UEInfoServiceContext.java:62)
at com.sun.corba.se.spi.servicecontext.ServiceContext.write(ServiceContext.java:97)
at com.sun.corba.se.spi.servicecontext.ServiceContexts.writeMapEntry(ServiceContexts.java:340)
at com.sun.corba.se.spi.servicecontext.ServiceContexts.writeServiceContextsInOrder(ServiceContexts.java:308)
at com.sun.corba.se.spi.servicecontext.ServiceContexts.write(ServiceContexts.java:265)
at com.sun.corba.se.impl.protocol.giopmsgheaders.ReplyMessage_1_2.write(ReplyMessage_1_2.java:192)
at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.createResponseHelper(CorbaMessageMediatorImpl.java:2217)
at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.createResponseHelper(CorbaMessageMediatorImpl.java:2180)
at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.createSystemExceptionResponse(CorbaMessageMediatorImpl.java:2105)
at com.sun.corba.se.impl.protocol.CorbaServerRequestDispatcherImpl.dispatch(CorbaServerRequestDispatcherImpl.java:266)
at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.handleRequestRequest(CorbaMessageMediatorImpl.java:1698)
at com.sun.corba.se.impl.protocol.SharedCDRClientRequestDispatcherImpl.marshalingComplete(SharedCDRClientRequestDispatcherImpl.java:171)
at com.sun.corba.se.impl.protocol.CorbaClientDelegateImpl.invoke(CorbaClientDelegateImpl.java:147)
at org.omg.CORBA.portable.ObjectImpl._invoke(ObjectImpl.java:475)
at com.sun.jmx.remote.protocol.iiop.ProxyStub._invoke(Unknown Source)
at org.omg.stub.javax.management.remote.rmi._RMIConnection_Stub.getAttribute(Unknown Source)
at javax.management.remote.rmi.RMIConnector$RemoteMBeanServerConnection.getAttribute(RMIConnector.java:901)
at MethodResultTest.test(MethodResultTest.java:143)
at MethodResultTest.main(MethodResultTest.java:93)
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:601)
at com.sun.javatest.regtest.MainWrapper$MainThread.run(MainWrapper.java:94)
at java.lang.Thread.run(Thread.java:722)