As of 0.6.4, wpa_supplicant includes a driver for the wifi chip in the PS3, thus allowing the use of WPA encryption on the platform. However, the driver is currently disabled in Fedora. The fix should be as simple as adding CONFIG_DRIVER_PS3=y to the config file.
The WEXT driver should work correctly with the PS3 Gelic wireless driver as of 2.6.27 kernel and wpa_supplicant 0.6.4, both of which ship with rawhide. The "ps3" wpa_supplicant driver is deprecated as it was used before the kernel had WEXT support for IW_ENC_CAPA_4WAY_HANDSHAKE. Please let me know if the WEXT driver doesn't work by reopening this bug, and then we'll try to pin down where the problem is.
Indeed, in F10 Beta, WPA works out of the box. Thanks.