IBM T21 Ethernet controller not working under Debian Etch

[ozmate <debianhelp.20.ericm@neverbox.com>]

Hi,

I've installed Etch on an IBM T21 laptop. Everything works just fine,
how great it is to work with such a complete operating system.

But unfortunately I'm struggling with the embedded NIC card.

lspci -v
Ethernet controller: Intel Corporation 82557/8/9 [Ethernet Pro 100] (rev 09)

It appears in the Networking configuration panel. But if:

1/ if I set it to dhcp: I don't have any IP Address.
ifconfig -a shows me that no IP address has been assigned

2/ if I set it to static: I can't ping anything
ifconfig -a shows me that the correct settings are set, though.

Now, if I plug an PCMCIA Xircom EtherJet card in the laptop,
it is recognized and works fine. DHCP ok, Static IP ok. I can
access the outside world...

I've surfed the Internet to find any solutions, but with no lucks.
Any help would be much appreciated.

Thanks