linux - Ubuntu intrepid - static IP networking keeps restarting with DHCP

I've got a linux box with a static IP configured that seems to be ok. The static IP address works for a few hours, and then sets itself back with (what seems like) whatever DHCP tell it to use.

Here's my /etc/network/interfaces

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 10.0.0.101
netmask 255.255.255.0
network 10.0.0.0
broadcast 10.0.0.255
gateway 10.0.0.254

Any ideas?