I have the exact same outcome after adding the /etc/dhcp3 -> /etc/dhcp symlink. The customization IP address and hostname are configured but the nameserver and search entries are missing leaving a blank /etc/resolv.conf file.
cat /etc/network/interfaces
iface lo inet loopback
auto lo
auto eth0
iface eth0 inet static
address 192.168.1.221
netmask 255.255.255.0
up route add default gw 192.168.1.1
cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
This same customization spec works as expected w/ ubuntu 12.04.