Proxying WCF service through the Fiddler

Set Fiddler as system wide proxy with preferred port (e.g. 8888).
Change app config of the WCF service host application as follows

<system.net>
  <defaultProxy
            enabled = "true"
            useDefaultCredentials = "true">
   <proxy autoDetect="false" bypassonlocal="false" proxyaddress="http://127.0.0.1:8888"    usesystemdefault="false" />
  </defaultProxy>
</system.net>

That's it.