Comment 2 for bug 427775

One issue with this is that gnome-system-tools/system-tools-backends is set up to edit /etc/ntp.conf by default (although it's not obvious to me that it does so quite correctly, but anyway ...). Perhaps it would be more straightforward for /etc/network/if-up.d/ntpdate to fall back to /etc/default/ntpdate.dhcp if it doesn't find any ntp.conf-style server configuration?