Yea, the Omnia is capable of recording videos at widescreen format, 5:3 ratio. Although not standard ratio, this resoluation allows the recorded video to be played in full screen

1. Use a registry editor, go to HKCU/Software/Samsung/Camera
2. Change the value of VideoSize to 1653, and you can now record 400x240 videos :D


Note: you will need to go to video mode at least once before you could see the registry entries. Changing the setting in the camera will set it back to the original resolution. In addition, the camera setting does not reflect the new resolution.

Thanks andylyf for the tips :)