Flash Uploader Times out

I have a flash uploader I created with flex on my site. It works great, except with very large files. Some of our clients need to upload files up to 1 or 2GB in size.

What appears to be happening is the browser seems开发者_StackOverflow to time out, but I cant get an error it just keeps thinking its uploading.

If the user moves the mouse around on the browser page, the upload will complete successfully.

Any Ideas?