Wild guess: Hotplug?
I was going to answer exactly the same :-) Check this http://linux-hotplug.sourceforge.net/?selected=hotplug
Caused by the new hotplug version with kernel 2.6.x. I am not running hotplug at boot, only used for hwd, and now its trying to active.... that's not fair.
Well, if the kernel has hotplug support it will call /sbin/hotplug at every hotplug event, so you don't have much choice it seems.
The hotplug script at boot is only for coldplugging.
I have the same "How do I bring interfaces up ..." message, but I did not quite understand from this discussion what to do ... recompile the kernel? Reconfigure hotplug? Some hint will be appreciated!
Its not yet solved. There must be a place to stop kernel to activate the hotplug "without re-compiling the kernel".
The matter is in the new version of hotmail. The earlier version was fine. When I get time I will check on it.
Anyway, if you don't want to use hotplug, but only have it installed, then add something like "echo /bin/true > /proc/sys/kernel/hotplug" to your rc.local.
If you want to get rid of the message, but stil use hotplug, then edit /etc/hotplug/net.agent (That's the hotplug package maker's responsibility though).