Hi
Reading the user manual for the Nokia card they rely pretty heavy on the SIM
The card may be trying to do EAP-SIM then when this fails trys again using static WEP ??? Not sure if the Nokia card will do that, it was not clear in their user manual
The other thing I saw was they have a built in VPN client that may also be causing this but it is less likely than the first suggestion.
Try turning off the sim authentication and see if the problem still occurs. NB this may affect your GPRS connection so please also test that after the changes