From: <span tal:replace="structure options/From" />
<tal:block tal:condition="options/To|nothing">To: <span tal:replace="structure options/To" /></tal:block><tal:block tal:condition="options/recipients|nothing" tal:replace="structure options/recipients"></tal:block>
Subject: <span tal:replace="options/Subject" />
Content-Type: <span tal:replace="options/ContentType" />; charset=<span tal:replace="options/charset" />
Mime-Version: 1.0

<span tal:replace="options/body">message...</span>

<span tal:replace="options/footer|nothing"></span>