On Evolt.org, there's this new tutorial that steps you through the implementation of the TMX standard to create localization for your scripts.

One of the main concerns of internationalization consists of separating the main source code from the texts, the labels, the messages and all the other objects related to the specific language in use. This facilitates the translation process as such as all the resources related to the local language context are well identified and separated.

In a global market the costs to translate and update the texts (including labels, messages, menu elements and so on) can easily become quite high. This is the context where the TMX standard comes to help by applying to the translation and management process of these texts the concepts of reuse, increase of consistency, and the shortening of the production cycle. All this with the added bonus of cutting the development costs.

They give you the XML structure for the example they're working with and the code to get it all working. They also do a great job of explaining how the standards all work. The code is relatively undocumented, but is clear enough to be easily included and used on any site.