IIS 7.0 and IHttpModules

When using IIS 7.0 an HttpModule needs to be configured in the

<system.webserver>
  <modules>
    <add type="HelloWorldModule" name="HelloWorldModule" />
  </modules>
</system.webserver>

In addition to the section for IIS 6.0. This was troubling me for several days in China using Windows Vista until I checked the help file on IHttpModules!