hum, that's strange.
Could you post your System.log ?
If you have a Mod, try renaming the Mods folder to Mod.bak, to be sure it doesn't interfere with the Pak02 from the patch, and then launch the game again.
If you installed a Mod outside the Mods folder, then hum, it's bad...
Also, be sure to close the game before installing the patch.