You will need stationary firmware version 1.7.0 or newer in order to get WEP to work on prism2 cards. The linux-wlan-ng package has tools for loading newer firmware into the card RAM (without flashing), but I don't know how well this works for PCI cards. Generally we only recommend linux-wlan-ng for the USB cards, and the others should work better with hostap.
You could try prism2 by installing the linux-wlan-ng-source package and build for PCI (default is USB only). But I'd say you'd rather try to get hostap to work.
You will need stationary firmware version 1.7.0 or newer in order to get WEP to work on prism2 cards. The linux-wlan-ng package has tools for loading newer firmware into the card RAM (without flashing), but I don't know how well this works for PCI cards. Generally we only recommend linux-wlan-ng for the USB cards, and the others should work better with hostap.
You could try prism2 by installing the linux-wlan- ng-source package and build for PCI (default is USB only). But I'd say you'd rather try to get hostap to work.