![:P](http://forum.falloutstudios.org/public/style_emoticons/default/tounge.gif)
A little more inside info for those interested:
The cause of this was that the HTTP headers weren't being sent properly due to a small script bug. Thus, the MIME type wasn't reported correctly for the file, instead everything was being sent as text/html. The reason it worked in Internet Explorer might be that IE ignores the MIME type when it sees that the content is really a picture. Firefox however takes the MIME type seriously (as it should!) and displays it as HTML when told to do so.