<script src="/js/lang/wikiedit.<?php $this->user_lang;?>.js"></script>	

-> js/ folder due handler restrictions

gets cached once, right and we put this way all our message sets for WikiEdit and
upload.js,

but it requires always this extra line, is there a way to let the original JS file load the language file,
if we pass the parameter when loading the file?

 <script src="/js/wikiedit.js?lang=<? echo $this->user_lang; ?>"></script>