network device confusion with usb wireless (wlan-ng)

[Matt Price]

hi folks,

running on dapper with a self-rolled kernel, on ppowerpc (blue &white
g3).

having trouble with the linux-wlan-ng drivers and an ashton airdash usb
802.11b adaptor.  after some work, I have it functioning, and can do
certain things over the interface, e.g. pinging and sshing from outside.
THisi s after following the directions in the linux-wlan-ng README and
also some from here
( http://ubuntuforums.org/archive/index.php/t-4041.html).  

 However, I don't see a way to get internal programs to use and
recognize wlan0.  For instance, if I deactivate eth0 in network-admins,
firefox won't load anything, and I can no longer ping outfrom the
machine.  There seems in anycase to be some kind ofwierd confusion
between network-admins (the gnome network tool)
and /etc/network/interfaces.  SO for instance, right now I have wlan0 up
and running, which is great, and ifdown thinks that eth0 is down.
However network-admins tells me that eth0 is in fact still "active"; and
if I, e.g., diconnect my ethernet cable physically, all internet
connections are lost.  

Soon this ocmputer won't have a physical ocnnection any more, so here's
whatI wantto have happen:

- eth0 stay disabled.
-wlan0 become default inet interface for all outgoing & incoming
connections.  

I don't really care whether this behaviour is configurablethrough the
gnome network interface or not, but I would like to have it work
reliably.  

I'm happy to provide moredetail if anyone thinks that'll help.  

THanks,

matt