I would not say it is strange location. Since you haven't provided any location really, the natural place to look for is the Java classpath. If you want to change it somehow, you need to use fully qualified name for base name, i.e.:
ResourceBundle.getBundle("com.my.company.localizedStrings", Locale.GERMAN);
The only doubt I have, since you probably use something like J# is whether that will work. It should.