I have a card which can transmit on any of 2.4[123456]2 GHz.  (that
list may change).

How should this done in a device-indepent way?  

ifconfig wl0 freq 2.422GHz

???
-- 
Matt Thomas               Internet:   matt@3am-software.com
3am Software Foundry      WWW URL:    http://www.3am-software.com/bio/matt.html
Nashua, NH                Disclaimer: I disavow all knowledge of this message