Add the following to the biztalk config for tracing all the WCF calls and messages
<system.diagnostics>
<sources>
<source name=”System.ServiceModel.MessageLogging”>
<listeners>
<add name=”messages”
type=”System.Diagnostics.XmlWriterTraceListener”
initializeData=”c:\wcfTrace.e2e” />
</listeners>
</source>
</sources>
</system.diagnostics>