I should deliver the default catalog as a SH3F file too. [:)]

At the moment, you can quite easily get rid of the default furniture catalog of Sweet Home 3D, by following these steps:
- Ensure you installed Sweet Home 3D from its installer (not with Java Web Start).
- Remove the file named Furniture.jar from Sweet Home 3D installed files. Under Windows and Linux, this file can be found in the lib subdirectory of Sweet Home 3D installation directory ; under Mac OS X, choose first Show Package Contents item in the contextual menu of Sweet Home 3D application icon, and go to the subfolders Contents > Resources > Java to remove Furniture.jar.
- Relaunch Sweet Home 3D, all default furniture will be gone.

Reusing the furniture contained in the Furniture.jar file is less easy ; here are the big steps:
- rename Furniture.jar as DefaultFurniture.zip,
- in Furniture.zip rename the entry com/eteks/sweethome3d/io/DefaultFurnitureCatalog.properties as PluginFurnitureCatalog.properties (in root directory),
- rename DefaultFurniture.zip as DefaultFurniture.sh3f, and use this file as any SH3F file.

If you can't achieve it, you'll have to wait the release of a SH3F file containing default furniture (this may happen in the coming weeks).