There is an issue that you may get when you try to use 2 modules above: You did not see anything in the directory /proc/acpi/sony.
Fedora 8 goes with the new driver for sony laptop: sony-laptop module.
Its location: /sys/devices/platform/sony-laptop
You can use command (at root): $lsmod
To see the whether the module sony-laptop is loaded in your F8 or not.
With the module sony-laptop in your F8, you can now change the screen brightness using gnome-power-manager or just create the applet brightness (or whatever, I forgot the name) and change it manually.
The problem of sony-laptop that me and some people get is that we cannot make the fn key work with sony-laptop module (already did like in the wiki says, but still not work).
For that reason, If you want to use the 2 modules above, read continue:
If you see the module sony-laptop is loaded, when you compile the 2 module sony_acpi and fsfn abouve, there will be nothing in /proc/acpi/sony.
The solution I know (I did not test it) to make the sony_acpi and fsfn work again is you must turn off module sony-laptop before you compile 2 modules above, and there will be normal again.
P/s: If any one have better solution, please let me know by posting in here. Thanks.