[Samba] Change network interface from wlan0 to eth0

[gabriele]

Hi to all:),
I have a desktop with Ubuntu 9.10 and a laptop with Win 7. They're both 
connected to Internet with their WIFI interface. I use Samba to send 
files between these computers and it works fine but I'd like to use 
Samba with a crossover cable. I connected them with this cable and 
modified the /etc/samba/smb.conf writing in [Networking] section:
interfaces = eth0
bind interfaces only = yes

and, after that,

sudo /etc/init.d/samba restart

but Samba continues to use wifi interface to connect my computers.
Can you help me? Thank you so much for your attention.
Gabriele