Connect to shared iTunes libary on sleeping Mac

Hi,

I have a MacBook on which I have my iTunes library with home sharing activated. If the Mac is running, I can stream the music to my iPad using the Music app or remotely control the library via Apples Remote app. Now, when the Mac is sleeping and after a few minutes, I am not able to connect to the library any more. I have checked that my Mac wakes up on network activity and it is on power (not running on battery).

Question: How to access the library from any other device (Mac, iDevice) without waking the MacBook by hand? Is Wake-on-LAN needed or should it work with my current setup? Or did I miss something (e.g. preferences)?

Cheers

Phil