From: expiredpgp1@example.com
To: pgp2@example.com
Cc: pgp3@example.com
Message-ID: <649194c00_140d322607069c@MacBook-Pro.fritz.box.mail>
Mime-Version: 1.0
Content-Type: multipart/signed;
 boundary="--==_mimepart_649194c00_140d32260708d4";
 micalg=pgp-sha1;
 protocol="application/pgp-signature"
Content-Transfer-Encoding: 7bit

This is an OpenPGP/MIME signed message (RFC 3156)
----==_mimepart_649194c00_140d32260708d4