Need Help with WiFi Options

I have a Zaurus SL-5500, latest kompany rom and kernel, with a Symbol Spectrum24 WiFi card

Here's my problem:

At school we have a number of wireless access points. I would like to be able to connect to any one of them by enableing the "Any" essid option in the wireless configuration. When i do this, it finds the access point, its mac address, gets a signal of around 98%, and the quality of that signal is 54%. All seems good - untill it complains that "No Connection detected. Check your WEP Key settings, and/or your tcp/ip settings."

now here's the odd part - if i specify the essid of the access point, it works flawlessly. this tells me that my wifi card is still intact, and that the settings for tcp/ip and WEP key are correct.
(yes we use WEP at school. I would sooner use VPN but try telling that to the school network admin)

does anyone have any ideas on this?