Jantje:
I have been running with the proposed changes fine but now it starts failing.
Not sure what is going on but it looks like avahi stops working on the yun.
...
avahi-daemon using dbus has bad reputation, might be worth to try:
nano /etc/avahi/avahi-daemon.conf
[server]
enable-dbus=no
#host-name=foo
#domain-name=local
...
/etc/init.d/avahi-daemon restart