Ubuntu Hardy and no-working wireless on T42

[dtm]

Hallo to everybody,
I've got a serious problem with wireless connection on my thinkpad T42. Altough on Windows everything works good, using Ubuntu my wireless system is perfectly recognized by the OS, finds the signal but it's not able to ping the router, so no Internet. Ethernet connection is perfect. Searching the web i discovered this page, which claims i should have some problems with kernel 2.4, on the contrary using the new one 2.6 every trouble concerning cisco firmware should be solved.
False: Slax 5.1.8.1 allows me to reach the net (kernel 2.4!!!) while Ubuntu does not (since Dapper Drake 6.06).
My firmware version is 5.41 and I can't upgrade it (cisco site deny me to download anything); the wireless module on Ubuntu and Slax is the airo one.
Same problem here.
In conclusion:
- is there any way to upgrade firmware, hoping it could solve the problem?
- does somebody know anything that could help me?
Thanks for patience and sorry for my awful english,
dtm

[Volker]

I'd suggest you try to make it work on an unencrypted network first.

To get the encryption working you probably have to try flashing different versions of the cisco firmware until you find one that works.

Or get a new wireless mini-pci card.

[dtm]

thanks for the reply!
Unfortunately I am sure it's not an encryption problem, I tried opening the network first.
About the cisco firmware, I am not able to find out where to download it.