...I hate to say this but I have a strong feeling your wifi card needs a non-free driver.
I obviously don't recommend you using it, so yeah, the link I gave you is your best bet if you want to be extra secure.in the future though, I do suggest getting something more free software friendly though.
ask around here and you can get some ideas for the future. but as for right now the tehnoetic wifi adapter is the safest way to do it.
