[Gimp-user] turning off thumbnail in jpeg saves; deleting a thumbnail?

[Gary Aitken <gimp dreamchaser org>]

Is there any way to turn off the jpeg thumbnail 
when writing out a file using
  file-jpeg-save?  
Otherwise, a small web image can be large when generated by copying from an
existing image which has a thumbnail.
In my case, the source image is coming in via ufraw.

It's not clear to me whether the thumbnail I'm getting is created by GIMP
or sent to it from ufraw.
If it's being created by gimp,
is there a way to delete the thumbnail from an image? 

Or does one have to create a new empty image
and copy only the active layer from the existing image to it?
Will that even solve the problem?
Problem with creating a new image is all the exif data, etc, is lost.

Thanks,

Gary