The Seam manual tells us that resource bundles for localisation should be in the old style format (pre-1.6) in the latin1 encoding with \u escapes for UTF-8 characters. This is obviously less than ideal for foreign language editors, which is why Java 1.6 came with many ways to fix this. It supports loading PropertyResourceBundle with any encoding (this could be the old format but in UTF-8), or even in XML format which would allow the encoding to be specified in the file.
Do you think we could get that candy in Seam? It would be great if XML bundles were supported alongside old-style plain-text latin1 bundles, and if plain text bundles could have their encoding specified in Seam's components.xml file.