xymon test dependencies

From the xymon.com webpage is this snippit...

Combined super-tests and test interdependencies ... Tests can also be configured to depend on each other, so that when a critical router goes down you will get alerts only for the router - and not from the 200 hosts behind the router.

I'm not seeing how to set this type of testing up, basically event correlation, so that if a switch goes down, hobbit knows not to send alerts for each connected host.

Can some point me in the right direction, i.e. specific man-page, or just show me an example of how to configure this?

Thanks, Taylor