I happened to fire up Console.app today and found lots of these messages in the log:
13/12/2011 22:54:09.291 de.devolo.networkservice: [pktifc] write: Device not configured
They are being generated 8 times every 5-second interval. My network is setup as shown in the attached diagram where there are two Devolo powerline network adapters connecting the wireless access point upstairs to my modem/wifi access point/dhcp server device downstairs. I want to know what these messages mean, whether they are a problem and if so, how to solve it.