Extraneous Software has released v 0.56 of the Viha Controller a pref pane to unload and load the viha drivers to pit your apple airport card into promiscous mode.
I haven't played with it yet, but will soon.
site:
http://extraneous.us/software/vihacontroller/index.htm
driver:
http://extraneous.us/download/vihapane-056.tgz
source:
http://extraneous.us/download/vihapane-source-055.tgz
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