Special thanks to Zangieff, whose finding made this hack possible.
You can actually use this hack to get any official firmware update available on Kies installed on your phone regardless of your phones region (assuming you have the correct data available).
Check the replies for an appropriate region with code. If you can't find one, it's likely not discovered yet (or has not had any kind of upgrade by Kies).
1) Start Kies. Start the upgrade software and make sure the upgrade software detects your phone properly.
2) If your preferred region requires you to have test mode ON, press CTRL-ALT-U-P. You should get a popup window stating that Test mode is ON. (Test mode is disabled in the most recent Kies versions, as far as I know it's also unused, so there's no real benefit in downgrading to get it)
3) Now close down the update program (Do not close Kies).
4) Run regedit, and browse to the key HKEY_CURRENT_USER/Software/Samsung/Kies/DeviceDB/. Under it you have a bunch of numbered keys, find the one that contains the relevant keys (HIDSWVER and ProductCode). If you find more than one HIDSWVER and ProductCode modify the number that also have a key with the IMEI of the phone you wish to upgrade.
5. Replace HIDSWVER and ProductCode with the apropriate values.
6. Launch the upgrade software, and update your firmware.
Enjoy your new firmware.