No you shouldn't. This is a very old language pack you have found.
We supply a download for a UK English Language pack which you can find here...
http://sarkpbx.com/sail/languagepack/This is the only alternative language pack we offer. You can, however, fit any language pack you wish to the underlying asterisk image (at your own risk - we won't support it for you). As far as we know, we do not generate any sounds which are not supported by the standard US English language pack, which is usually the reference for all other packs.
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