Network connection doesn't work (etch on Thinpad 600x, Xircom card)

[Martin Möller <exsomnis@gmx.de>]

I've tried to install Debian etch on my Thinkpad 600X for several times.
Without success. My network card is a Xircom combined Cardbus
modem/ethernet (rbem56g-100). I also tried a WLAN PCMCIA card, no
success either. Here's what happens:

The (xircom) card is found and bound to eth0. The LED on the card and
the DSL modem turns on and flashes correctly if I try to ping the modem
for example, but: DHCP assignment fails. If I give the card a static IP
address, I can only ping loopback. Same thing with the WLAN card
(ndiswrapper).

I've installed Sarge to see if it works there and it did. When
upgrading to etch, everything works until the hotplug/udev thing gets
updated.

When booting from an etch Install-CD, the logs show
"exec of program /lib/udev/net.agent failed"

Same problem with a "grml 0.7"-CD. On Ubuntu 6.06, everything works.

Any ideas would be greatly appreciated!

-- 
Martin Möller 
Using Debian etch/testing for amd/64