NIS America has confirmed that the European version of Disgaea 3 is finally getting a trophy patch. In addition, NIS America has also revealed that the patch will be retroactive so some trophies will automatically unlocked, providing the requirements are met, once the patch is installed. If you are lucky, you may not have to play through the game again.
The patch will be available to download in Europe on May 13th 2010. You can check out the complete trophy list here, and see how many trophies you have met the requirements for.