Strange characters when transmitting JavaScript files

[Remo Laubacher]

Hello Nginx Users,

I'm new to nginx. I really like what I've seen so far, however there is one 
problem I couldn't solve during my tests.
One application uses the FCKeditor and some JavaScript files are transmitted 
with some strange characters.
It only happens with several files, not with every JavaScript file!

fckeditorcode_gecko.js looks like this:
/*
 * FCKeditor - The text editor for Internet - http://www.fckeditor.net
 * Copyright (C) 2003-2007 Frederico Caldeira Knabben

The three characters at the beginning shouln't be there of course.

I'm trying to solve this problem for quite a while but without much success 
so far. What I've tried:
- rebooted system
- recompiled nginx (latest version)
- updated fckeditor to the latest version
- "rewrote" javascript (open with vi and write to a new file)
- played with mime type
- renamed file to .txt (didn't change anything)

What else could I try?
Thanks a lot!
Remo