Problem when display alert whoth special chars in a source f

[wxdqz]

Hi guys,
In my HTML page, I have somewhere this:
<SCRIPT type="text/javascript" src=http://www.webdeveloper.com/forum/archive/index.php/"/blabla/theSource.js" language="javascript">

In my source fil, I have somwhere an alert:

alert ("d閏imal"); //sorry, I'am french ;-)

when I run my code I get an alert but with something like:

d<some chinese chars>mal


any ids ?