Comment 9 for bug 149869

jerrylamos, policy for gutsy have changed and you need to have interfaces controlled by n-m completely commented out ot /etc/network/interfaces. From my system:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
#iface eth0 inet dhcp

Can you check/attach your interfaces file?