For some reason I am having a problem with my wirelees card's wep encryption. The card works and can see the access points. When I try to enter the wep key with "iwconfig" it says:

Error for wireless request "Set Encode" (8B2A) :
SET failed on device eth0 ; Operation not supported

If I look in dmesg it puts out:

ieee80211_crypt_wep: Unknown symbol crypto_alloc_tfm
ieee80211_crypt_wep: Unknown symbol crypto_free_tfm

I am not sure what to do I have tried using different versions of the ipw2200.sourceforge.net files but it won't work. I have changed what the INSTALL file said to change in the kernel and compiled it but for some reason I get this error. If someone could help me out it would be much appreciated.

If this thread is correct, it could be that you have to add another module.

Try modprobe tcrypt and see if that helps the situation.