I unfortunately encountered this using the latest version of s3cmd cloned from github. Any help would be appreciated.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    An unexpected error has occurred.
  Please try reproducing the error using
  the latest s3cmd code from the git master
  branch found at:
    https://github.com/s3tools/s3cmd
  If the error persists, please report the
  following lines (removing any private
  info as necessary) to:
   s3tools-bugs@lists.sourceforge.net
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Invoked as: /usr/bin/s3cmd -c /home/ec2-user/.s3cfg-myconf sync --delete-removed s3://mybucket /var/backup/mystuff/Problem: OSError: [Errno 20] Not a directory
S3cmd:   1.5.0-alpha3

Traceback (most recent call last):
  File "/usr/bin/s3cmd", line 2181, in <module>
    main()
  File "/usr/bin/s3cmd", line 2106, in main
    cmd_func(args)
  File "/usr/bin/s3cmd", line 1260, in cmd_sync
    return cmd_sync_remote2local(args)
  File "/usr/bin/s3cmd", line 947, in cmd_sync_remote2local
    seq, total_size = _download(remote_list, seq, remote_count + update_count, total_size, dir_cache)
  File "/usr/bin/s3cmd", line 906, in _download
    raise e
OSError: [Errno 20] Not a directory

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    An unexpected error has occurred.
  Please try reproducing the error using
  the latest s3cmd code from the git master
  branch found at:
    https://github.com/s3tools/s3cmd
  If the error persists, please report the
  above lines (removing any private
  info as necessary) to:
   s3tools-bugs@lists.sourceforge.net
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!