ethernet not working right

[Forest Fisher <Forest.Fisher@oberlin.edu>]

I just installed Debian (Woody) on my new laptop with
the 2.4.18 kernel.  My laptop is a hp pavilion
ze4560us and the ethernet card is National
Semiconductor Corporation DP83815.  I set the
ethernet up by editing /etc/network/interfaces,
changing the first line to auto lo eth0 and adding,

iface eth0 inet dhcp

Then,

#modprobe natsemi

lspci recognizes the card.  But then,

#ifconfig ext0 up

gives me

eth00: ERROR while getting interface flags: No such
device

#ifup ext0

gives me

Ignoring unkown interface ext0=ext0

when I try to run dhclient I get similar results.
For example,

#dhclient

gives me

eth0: autonegotiation did not complete in 4000 usec.
eth0: link up.

afterward ifconfig shows eth0 but there is no IP.
Again,

#dhclient

gives me

"ext0: ERROR while getting interface flags: No such
device

I also tried replacing the line

iface eth0 inet dhcp

with

iface_eth0="dhcp"

at the suggestion of a friend, but this gives me the
same results.  Can anyone help please?

Sincerely,
Forest Fisher