Simon Brandhof asks: Is it possible to discover bundles at runtime in cal10n ? I can't list all the available locales of LocaleData at compile time. Thanks Answer: Yes, as long as you don't expect automatic verification, @LocaleData information is entirely optional. The default implementation of IMessageConveyor, namely MessageConveyor, will discover bundles for any locale. For example, here is a mininal enum: @BaseName("minimal") public enum Minimal { A; } Assuming the file "minimal_de.properties" exists on your class path, and contains: A=etwas auf deutch the following code will return work: MessageConveyor mc = new MessageConveyor(Locale.GERMAN); assertEquals("etwas auf deutch", mc.getMessage(Minimal.A)); However, the encoding for minimal_de.properties will be assumed to be the system's default encoding. You can also have a mixed approach, where you specify some encodings and not others. @BaseName("minimal") @LocaleData( defaultCharset="UTF8", value = { @Locale("en_UK"), @Locale("fr_FR") } ) public enum Minimal { A; } In the above example, tooling which comes with CAL10N will verify the consistency for en_UK and fr_FR. The default encoding will be "UTF8" for all bundles, including the bundle "minimal_de.properties" for German (which remains undeclared). You could also mix default encoding, bundle specific encoding and undeclared bundles. For example, @BaseName("minimal") @LocaleData( defaultCharset="UTF8", value = { @Locale("en_UK"), @Locale("fr_FR"), @Locale(value="tr_TR", charset="ISO8859_3") } ) public enum Minimal { A; } In the above example, tooling which comes with CAL10N will verify the consistency for en_UK, fr_FR and tr_TR. The default encoding will be "UTF8" for all bundles, including the bundle "minimal_de.properties" for German (which remains undeclared) but excluding "minimal_tr_TR.properties" (Turkish) which will be encoded in ISO8859_3 (Turkish). HTH, -- Ceki Gülcü Logback: The reliable, generic, fast and flexible logging framework for Java. http://logback.qos.ch