You can disable the coaster brake, use a chain tensioner and use the T3 just for the gears.
See:
http://www.bikeforums.net/showthread...=brake+coaster
http://www.bikeforums.net/showthread...=brake+coaster
Some hubs make dis-/reassembly difficult apparently, see:
http://www.bikeforums.net/showthread...=brake+coaster
You might want to contact dober, he seems to know his stuff.