When running s3cmd to add headers, if the object has an existing header that has unicode characters it will fail.

We store user uploads with a hashed object name in a bucket and during upload we add a header for Content-Disposition: filename="originalFileName.jpg". So if the user downloads the image later it gives them the original file name and not the ugly hashed object name.

I am attempting to add Cache-Control to all objects in the bucket and discovered that if you have a unicode character already in the headers (in our case in the originalFileName.jpg) it will fail with the decode error.

Is there a workaround or is this a known issue?