You don't. That's the answer. Cisco bridges do not support WPA2. WPA2 is only supported in access point roles. This is a big issue for some of my customers and I have to use other vendor solutions where WPA2 is required (Defense contractors and government use).
As much as I would love to help you I won't push someone else's product on the Cisco forum page. I would call Tessco or Gigawave and ask for assistance. They will tell you what bridges are out there that support WPA2 in bridge mode.