How do you set the creation and modification date for a file in AIR?

Question

I'm creating files in an AIR application like this:

var file:File = File.documentsDirectory.resolvePath("myFile");
var stream:FileStream = new FileStream();
stream.open(file, FileMode.WRITE);
stream.writeUTFBytes(data);
stream.close();

This leaves the creation and modification dates on created files blank. Is there are way to add this information?