I have an app.config that looks like this:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
 <appSettings
    file="External.config" >
 </appSettings>
</configuration>

And External.config contains all my settings,  e.g.

<?xml version="1.0" encoding="utf-8" ?>
<appSettings>
 <add key="setup WebType" value="IIS" />
 <add key="setup UseEPG" value="Y" />
</appSettings>

The trouble is, when I update some settings and do a Configuration.Save()
the settings are written back to the app.config and not External.config. Is
this a bug, design feature, or is there a setting to alter this behaviour?
Using .NET 2

Thanks,
John