network-admin setup a wrong /etc/network/interfaces file for static network address

On hoary.
I setup my network this way :
- IP adress 192.168.1.105
- Mask 255.255.255.0
- Gateway : 192.168.1.1
- DNS : 192.168.1.1

When I quit the command 'route' give me this ...
    root@spirou:/home/oim # route
    Table de routage IP du noyau
    Destination Passerelle Genmask Indic Metric Ref Use Iface
    localnet * 255.255.255.0 U 0 0 0 eth0

The gateway has not been setup ...

If I try the command 'ifdown' on the interface ... I got that :
    root@spirou:/home/oim # ifdown eth0
    /etc/network/interfaces:15: too few parameters for iface line
    ifdown: couldn't read interfaces file "/etc/network/interfaces"

On the "/etc/network/interfaces" file, on line 15, I got that :
    # The primary network interface
    iface eth0 inet
        address 192.168.1.105
        netmask 255.255.255.0
        network 192.168.1.0
        broadcast 192.168.1.255
        # dns-* options are implemented by the resolvconf package, if installed
        dns-nameservers 192.168.1.1
        name Carte Ethernet
        gateway 192.168.1.1

If I change 'iface eth0 inet' to 'iface eth0 inet static' :
    # The primary network interface
    iface eth0 inet static
        address 192.168.1.105
        netmask 255.255.255.0
        network 192.168.1.0
        broadcast 192.168.1.255
        # dns-* options are implemented by the resolvconf package, if installed
        dns-nameservers 192.168.1.1
        name Carte Ethernet
        gateway 192.168.1.1

and then 'ifdown eth0; ifup eth0' ... everything is now working ....

So network-admin seems to break the "/etc/network/interfaces" file when setting
a static network setup.