JDK 1.6 causes StreamCorruptedException

@Stateless
@RemoteBinding (jndiBinding="ejb/EJBTestServiceServiceBean/remote")
public class TestServiceBean implements TestService {
private Logger logger = Logger.getLogger(getClass());
@TransactionAttribute(TransactionAttributeType.REQUIRED)
public Format getFormat()

{ logger.info("get format"); return DateFormat.getDateInstance(DateFormat.SHORT); }

}

Calling this service method causes (On the client):

java.lang.reflect.UndeclaredThrowableException
at $Proxy0.getFormat(Unknown Source)
at com.enfusion.ejbtest.test.Main.main(Main.java:18)
Caused by: java.rmi.MarshalException: Failed to communicate. Problem during marshalling/unmarshalling; nested exception is:
java.io.StreamCorruptedException: invalid type code: 00
at org.jboss.remoting.transport.socket.SocketClientInvoker.transport(SocketClientInvoker.java:306)
at org.jboss.remoting.RemoteClientInvoker.invoke(RemoteClientInvoker.java:143)
at org.jboss.remoting.Client.invoke(Client.java:525)
at org.jboss.remoting.Client.invoke(Client.java:488)
at org.jboss.aspects.remoting.InvokeRemoteInterceptor.invoke(InvokeRemoteInterceptor.java:61)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.aspects.tx.ClientTxPropagationInterceptor.invoke(ClientTxPropagationInterceptor.java:61)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.aspects.security.SecurityClientInterceptor.invoke(SecurityClientInterceptor.java:55)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.ejb3.remoting.IsLocalInterceptor.invoke(IsLocalInterceptor.java:77)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.ejb3.stateless.StatelessRemoteProxy.invoke(StatelessRemoteProxy.java:102)

Serializing the same object in the same VM using regular Java IP streams works fine.