Exception in HttpInboundMessageContext.close: java.net.SocketException: Socket closed

Apparently under VERY heavy load we get this error in a HTTP Business Service... still under investigation.

It's not using a nio muxer, so I don't this that the Patch 9552622 described in java.io.IOException: Broken Pipe Seen Frequently in WebLogic Server Logs (Doc ID 1476825.1) really applies...

####<Nov 20, 2013 9:10:28 PM CET> <Error> <WliSbTransports> <myhost> <osbpr1ms1> <[ACTIVE] ExecuteThread: '100' for queue: 'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <> <4cea82998b9a2c15:7ce38336:1427138d527:-8000-00000000000af294> <1384978228423> <BEA-381304> <Exception in HttpInboundMessageContext.close: java.net.SocketException: Socket closed
java.net.SocketException: Socket closed
        at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:99)
        at java.net.SocketOutputStream.write(SocketOutputStream.java:136)
        at weblogic.servlet.internal.ChunkOutput.writeChunkTransfer(ChunkOutput.java:568)
        at weblogic.servlet.internal.ChunkOutput.writeChunks(ChunkOutput.java:539)
        at weblogic.servlet.internal.ChunkOutput.flush(ChunkOutput.java:427)
        at weblogic.servlet.internal.CharsetChunkOutput.flush(CharsetChunkOutput.java:298)
        at weblogic.servlet.internal.ChunkOutput$2.checkForFlush(ChunkOutput.java:648)
        at weblogic.servlet.internal.CharsetChunkOutput.write(CharsetChunkOutput.java:200)
        at weblogic.servlet.internal.ChunkOutputWrapper.write(ChunkOutputWrapper.java:148)
        at weblogic.servlet.internal.ServletOutputStreamImpl.write(ServletOutputStreamImpl.java:148)
        at org.apache.xmlbeans.impl.store.Cursor._save(Cursor.java:590)
        at org.apache.xmlbeans.impl.store.Cursor.save(Cursor.java:2537)
        at org.apache.xmlbeans.impl.values.XmlObjectBase.save(XmlObjectBase.java:223)
        at com.bea.wli.sb.sources.XmlObjectSource.writeTo(XmlObjectSource.java:92)
        at com.bea.wli.sb.sources.OutboundXOPSource.writeTo(OutboundXOPSource.java:116)
        at com.bea.wli.sb.transports.http.HttpInboundMessageContext.close(HttpInboundMessageContext.java:264)
        at sun.reflect.GeneratedMethodAccessor882.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at com.bea.wli.sb.transports.Util$4.invoke(Util.java:351)
        at $Proxy165.close(Unknown Source)
        at com.bea.wli.sb.pipeline.MessageProcessor.finishProcessing(MessageProcessor.java:398)
        at com.bea.wli.sb.pipeline.RouterCallback.onReceiveResponse(RouterCallback.java:108)
        at com.bea.wli.sb.pipeline.RouterCallback.run(RouterCallback.java:183)
        at weblogic.work.ContextWrap.run(ContextWrap.java:41)
        at weblogic.work.SelfTuningWorkManagerImpl$WorkAdapterImpl.run(SelfTuningWorkManagerImpl.java:528)
        at weblogic.work.ExecuteThread.execute(ExecuteThread.java:209)
        at weblogic.work.ExecuteThread.run(ExecuteThread.java:178)