Bonjour is done via mDNSResponder and this sucker prevents a Mac from sleeping when other Macs poll the serverlist in Finder. To fix this, use the following configuration

sudo launchctl unload /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist
sudo vi /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist

  .
  .
    <key>ProgramArguments</key>
    <array>
        <string>/usr/sbin/mDNSResponder</string>
        <string>-NoMulticastAdvertisements</string>
    </array>
  .
  .

sudo launchctl load /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist