Message resources

Greetings, There is a number of ApplicationResources_xx.properties in XWiki and it looks like all of them are different (contain different set of keys). Both ApplicationResources.properties and ApplicationResources_en.properties are in english and are mostly identical except for ~70 missing keys in _en file. Given that, I have two questions: 1. What is the "most supported" message resources file? 2. Are all messages from .properties used in XWiki, or some are redundant? If the latter, are there plans for removal of unnecessary keys for 1.0release? -- Best regards, Pavel