From: Some One <user@example.com>
To: Some One <user@example.com>
Subject: Test
MIME-Version: 1.0
Content-Type: Multipart/Mixed;
  boundary="top-level-boundary"

--top-level-boundary
Content-Type: message/rfc822;
  name="forwarded message"
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline

To: user@example.com
=46rom: Some One <user@example.com>
Subject: Forwarded Test
Content-Type: Multipart/Mixed;
  boundary=3D"nested-level-boundary"

--nested-level-boundary
Content-Type: text/plain;
Content-Transfer-Encoding: quoted-printable

Blah

--nested-level-boundary--

--top-level-boundary
Content-Type: text/plain;
  charset="utf-8"
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline

This is a test