21143 not working between 2 debian 2.1 machines

[=?iso-8859-1?Q?S=F8ren_Friis-Nielsen?=]

Problem: My two machines are unable to "see" each other on a 2-machine
network.
I have:
2 Debian 2.1 machines
Both have DEC 21143 chip cards and one cable running between them
They are connected without hub. The cables are crossed correctly because it
does work when they both run win98.
I've tried using the standard 2.0.36 kernel with tulip.o loaded and also
2.2.3 (both when it's compiled as module and when compiled directly into the
kernel).
The cards are detected correctly (as far as I can see) by the kernel but
when I do a ping from one of the two machines there is no response (as with
ftp, telnet and ssh) that it can "see" the other.
I'm not highly familiar with the inner workings of linux and I don't know C
og C++.
Does anybody know how to solve my problem?

Søren