WCF logging: Why isn't Close being called for TraceListener?

Question

I'm trying to log messages to my WCF service at transport level. I've followed some instructions I found on the net successfully, but now I want to implement my own trace listener that supports our in-house logging solution.

I've implemented a trace listener and I configure it using the app.config of my windows service hosting the WCF service. The following is the XML I use to configure the logging.

<system.diagnostics>
  <sources>
    <source name="System.ServiceModel.MessageLogging">
      <listeners>
        <add name="messages" type="my.namespace.AdvancedLogTraceListener, Tools.Logging, Version=2.0.3.1, Culture=neutral" initializeData="C:\Logs" />
      </listeners>
    </source>
  </sources>
</system.diagnostics>

...

<diagnostics>
  <messageLogging logEntireMessage="true" logMalformedMessages="false" logMessagesAtServiceLevel="false" logMessagesAtTransportLevel="true">
  </messageLogging>
</diagnostics>

All of this works pretty well. However: Our in-house logging solution is used like a class. This class starts a background thread to perform actions like log-cleaning, do the actual logging asynchronously, etc. The class requires a method named Close to be called when closing the application, which stops the internal processing and exits the thread.

The TraceListener class, which my TraceListener inherits from, implements a Close method. I've overridden this method as follows:

public override void Close()
{
   base.Close();
   this.logFile.Close();
}

Only that it doesn't work. The Close method of the TraceListener does not seem to get called. What should I do to ensure that I can call my Close method when the application hosting the WCF service is closed?