stick with Soenke Rohde (first -> http://soenkerohde.com/2008/07/flex-localization/
] ) - that looks quite good and is the common way. Solution 3 is pretty close to that too.
You'll also have problems if others are supposed to translate some for you if the translation is in the code. At the preferred solution you'll have properties-files dedicated to translation which you can easily had over for translation.