I have done this upgrade and it worked perfectly...what you'll need is a program from Amtel called ap configurator...it can be found here:

http://www.wi2600.org/mediawhore/nf0/wireless/utils/

You'll have to edit the program just a bit to get to the functions you need...you'll have to edit the snmpmanager.ini...so that the values that equal 0 will equal 2...then start the program...then there will be a radio section...go to that and set all the hex valuse to 80...upload new data, and whaalaa...100mW AP....for a good right up go here:

http://forums.netstumbler.com/newreply.php?action=newreply&threadid=1315