As you can see here http://cal10n.qos.ch/xref/ch/qos/cal10n/MessageConveyor.html#81 it realies on .toString(). My enums are richer than the basic manual depicted here thus I have overridden to string. Resouce trievals fails because the key name differs from the string represenation. Line 81 should work on #name() only and not rely #toString()