CSS not displaying in Firefox

Hello,

I am developping a social networking site in rails, it can be found at
the url www[dot]string[dot]be

My problem is that firefox doesn't seems to find/interpret the css
linked to it. Everything works fine in other browsers (IE, safari,
Opera) but not in firefox.

Does anybody have a clue ?

Your server sends CSS files with the wrong MIME type. From headers:

Request:

GET /stylesheets/scaffold.css?1163928878 HTTP/1.1
Host: www.string.be
<...>
Accept: text/css,*/*;q=0.1

Response:

HTTP/1.x 200 OK
Server: Apache/2.0.54 (Debian GNU/Linux) PHP/4.4.4-0.dotdeb.3 with
Suhosin-Patch mod_ssl/2.0.54 OpenSSL/0.9.7e
<...>
Content-Type: text/plain

So, instead of text/css server uses text/plain for CSS files. Check
your configuration.

Regards,
Rimantas