The latest SDK release (8.0.1) broke draw9patch, you’ll need to download swingworker and drop into android-sdk-directory/tools/lib/

You can download swingworker from http://code.google.com/p/dividere/downloads/detail?name=swing-worker-1.1.jar

Credit : http://groups.google.com/group/android-developers/browse_thread/thread/eb53f751f8361766/20dd69642e76c7b8