Pretty stupid to be able to attach a file to the message and you won't accept anything that can take an image - wanted to try and send the forum a screenshot of a weird looking thing on screen apparently attached to Norton 360 Premier Edition / IE9 and this format isn't accepted! I absolutely HATE "support" forums that stick in all sorts of restrictions which always manage to be exactly what I need to use!
And further - it would be nice if your "Attachments" field specified the accepted file formats instead of wasting users' times while they create, browse and load a file only to be told to buggar off it's the wrong format!