opscode/mini_s3 — pull request #14 by Jonty (2014-06-10 13:09:40+00:00)
Title: Prevent sending duplicate content-type headers

If the user specifies a content-type header that the file should be
served with from S3 a duplicate header containing the default value will
also be set by ibrowse, resulting in a signature failure and the S3
request being refused.