avahi-daemon should behave like openvpn

[nivw]

I added this line to avahi-deamon:
depend() {
before netmount nfsmount
use net
need dbus firewall
}

so the firewall will protect from allowing avahi WAN access.
but when ever a NIC goes up or down the firewall restarts.
in this case avahi may not start as the firewall is missing.
how to fix it?
can I mark it inactive as in openvpn?