ETag of the object uploaded via multipart upload does not match the CompleteMPU response from the transient blobstore

The local transient blobstore returns a correctly computed S3 MPU ETag when completing the upload, but a subsequent GET/HEAD request returns the MD5 of the whole object instead (not matching the ETag in the CompleteMPU response). Ideally, jclouds should store the MPU ETag and return it on GET/HEAD requests.

This behavior also manifests when using the filesystem blobstore if the extended attributes are not supported. In that case, there is nothing jclouds can do.