xymon test dependencies

[Taylor Lewick]

>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