This doesn't answer your direct question and I'm sure there is a way to
automagically do what you want, this would accomplish your goal. Someone
else may be able to answer better than me but you could do:
> Host "myhost" {
> hostname: 192.168.0.1
> Service Ping
messagedn: myhost (192.168.0.1) down
messageup: myhost (192.168.0.1) up
> }
Scott