file up to 4GB

Hello

I have a problem. I uploaded a 4gb file with my ftp into a folder. When I browse that folder in “Attach file” I find it. But when I select the file, the plug-in tells me that the file’s content weighs 0kb and the downloading doesn’t work.
http://www.unsungherothemovie.com/videos-videos/ (behind the scene)
thank you for your help