[cal10n-user] ch.qos.cal10n.MessageConveyorException

Hi, I'm getting the following message when I log: ch.qos.cal10n.MessageConveyorException: Failed to locate resource bundle [Bundle] for locale [en_US] for enum type [com.mycompany.Messages] at ch.qos.cal10n.MessageConveyor.lookup(MessageConveyor.java:115) at ch.qos.cal10n.MessageConveyor.getMessage(MessageConveyor.java:77) at org.slf4j.cal10n.LocLogger.error(LocLogger.java:167) I have a default Bundle.properties in my classpath but cal10n doesn't use it. Everything works fine when I have a Bundle_en_US.properties. Is there a way to tell cal10n to use the default Bundle.properties if a suitable bundle for the Locale it requires is missing?