many changes in new firmware

If u wan to have Chinese language...(APAC Region)
Then u need to make sure ur product code is Apac region.

1. Download Nemesis Service Suite Beta 1.0.38.14 (zip file, 6.3 MB).
2. Install it...During the installation pick Virtual USB Device from the Hardware Selection page.
3. Find 5800's APAC region product code (at internet or get the product code from ORI set in M'sia or sg.)
4. Open Nemesis Service Suite and click on Scan for new device in the upper right section of the application window.
5. Click on the Phone Info icon.
6. Click Scan in the middle of the application window.
7. Enter ur new product code in the Product Code text box. Click the Enable check box. Click Write to change your phone's product code.

8. Close the Nemesis Service Suite and open Nokia Software Updater application to update the firmware.

*If ur 5800 is ORI, thn ur product code is APAC Region pc. So, no need to change..juz straight away update by Nokia software updater. As for AP set, I'm not sure...some r Apac region product code but some not.   Oh ya, dun forget change back to ur original product code ya coz it might void ur phone warranty.