To test 10.6 Wake on Demand...

You can do the following to test and see if your setup supports the Wake on Demand.

1. In the Energy Saver System Preference Pane, check Wake for network access.
2. Open iTunes and turn on the iTunes library sharing. 
3. Put that computer to sleep.
4. On a separate Mac type the following command in Terminal

dns-sd -B _daap._tcp

You should see something similar to my screenshot. Notice that A/R is ADD. This means the service is still being broadcast by your router using Bonjour. It would say Rmv if the service was no longer being broadcast. You can test this by leaving this command running in terminal, waking up the computer providing the service and turning off iTunes Library sharing. 

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