Ubuntu – Multiple NICs with static IP address, default gateway problems

My server is running Ubuntu 10.04 64bit and have 2 NICs, my configuration is one interface for incoming/outgoing traffic of all the KVM guest running on this server, the other interface for different purpose.

I set both NIC card and the virtual bridge with static IP address; here is my /etc/network/interface

# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.5.10
netmask 255.255.255.0
network 192.168.5.0
broadcast 192.168.5.255
gateway 192.168.5.5

auto eth1
iface eth1 inet static
address 192.168.5.12
netmask 255.255.255.0
network 192.168.3.0
broadcast 192.168.3.255
gateway 192.168.5.5

auto br0
iface br0 inet static
address 192.168.5.11
netmask 255.255.255.0
network 192.168.5.0
broadcast 192.168.5.255
gateway 192.168.5.5
bridge_ports eth1
bridge_stp off
bridge_fd 0
bridge_maxwait 0

and here is my netstat -nr output

Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
192.168.5.0     0.0.0.0         255.255.255.0   U         0 0          0 eth0
192.168.5.0     0.0.0.0         255.255.255.0   U         0 0          0 br0
192.168.5.0     0.0.0.0         255.255.255.0   U         0 0          0 eth1
192.168.122.0   0.0.0.0         255.255.255.0   U         0 0          0 virbr0
0.0.0.0         192.168.5.5     0.0.0.0         UG        0 0          0 eth1
0.0.0.0         192.168.5.5     0.0.0.0         UG        0 0          0 br0
0.0.0.0         192.168.5.5     0.0.0.0         UG        0 0          0 eth0

I can not access the internet. I manually delete all the default gw using route del and add only 1 default gw for the device eth0 to access the internet

192.168.5.0     0.0.0.0         255.255.255.0   U         0 0          0 eth0
192.168.5.0     0.0.0.0         255.255.255.0   U         0 0          0 br0
192.168.5.0     0.0.0.0         255.255.255.0   U         0 0          0 eth1
192.168.122.0   0.0.0.0         255.255.255.0   U         0 0          0 virbr0
0.0.0.0         192.168.5.5     0.0.0.0         UG        0 0          0 eth0

The problem is when I reboot the server I manually run the route del command again and if I delete the default gw of eth1 in /etc/network/interface all the guest host can not access the internet.

Please help me how to configure that way