Set a terminator as a double new line (%NL;%NL. This causes Daffodil to throw an error on the CLI (and JAPI) that I don’t understand:

Parse Error: Term('%NL;%NL;') - element.MessageHeaders: Remote delimiter found instead of local!

Part of the DFDL:

<xsd:element name="TopLevel">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="MessageHeaders" dfdl:lengthKind="delimited"
dfdl:terminator="%NL;%NL;" type="xsd:string"/>
<xsd:element name="Body" type="xsd:string"/>
</xsd:sequence>
</xsd:complexType>
</xsd:element>

Input:

Date: Sat, 15 Feb 2013 08:54:52 -0500

This is the body