Adobe air on iOS - FileReference Download Error

I guys,

when I use the Download method of the FileReference class, everything works fine on Desktop and Android, but I get an error on iOS.

This is the code:

var req = new URLRequest(url); 
var localRef:FileReference = new FileReference(); 
localRef.download(req);

On iOS I'm getting an Alert:

Download Error
File downloads not supported.

I already tried to NavigateToUrl() and it asks save the file in Dropbox or another App.

How can I fix this error?

Thanks!