.htaccess redirect depending on refererer

[eluser]pixelknipsr[/eluser]
Hi,

I'd like to redirect users depending on their url referer with .htaccess. I've tried some stuff but it doesn't work.

Here's an example:
http://www.mydomain.com/start/ should redirect to http://www.mydomain.com/start/de.php
and
http://www.fr.mydomain.com/start/ should redirect to http://www.fr.mydomain.com/start/fr.php

That's what I tried so far:

Code:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /

    RewriteCond %{HTTP_REFERER} http://www.mydomain.com
    RewriteRule ^(.*)$/de.php [L]    
</IfModule>

Can someone help me on this?

cheerio