Let me know how your tests turn out. I haven't been able to personally fully test the bsd-airtools verison of airsnort to make sure it works, but I've heard from a couple people saying it does. Also, we'll be adding in a bsd port of prismdump fairly soon so those of you using bsd can use wepcrack to try and brute force keys (as well as ethereal and the other prismdump based apps that have been linux specific up until now).