<SOAP:Envelope
  xmlns:SOAP="http://schema.xmlsoap.org/soap/envelope/">
  <SOAP:Header
    xmlns:eb="http//www.ebxml.org/msg-header-2_0.xsd">
    <eb:MessageHeader id="123" eb:version="2.0"
      SOAP:mustUnderstand="1">
      <eb:From><eb:PartyId>123456</eb:PartyId></eb:From>
      <eb:To>
        <eb:PartyId eb:type="someType">987654</eb:PartyId>
        <eb:Role>
          http://rosettanet.org/processes/3A4.xml#seller
        </eb:Role>
      </eb:To>
      <eb:CPAId>uri:companyA-and-companyB-cpa</eb:CPAId>
      <eb:ConversationId>987654321</eb:ConversationId>
      <eb:Service eb:type="anyURI">
        bpid:icann:rosettanet.org:3A4v2.0
      </eb:Service>
      <eb:Action>Purchase Order Request Action</eb:Action>
      <eb:MessageData>
        <eb:MessageId>UUID-2</eb:MessageId>
        <eb:Timestamp>2000-07-25T12:19:05</eb:Timestamp>
        <eb:RefToMessageId>UUID-1</eb:RefToMessageId>
      </eb:MessageData>
      <eb:DuplicateElimination/>
    </eb:MessageHeader>
  </SOAP:Header>
  <SOAP:Body
    xmlns:eb="http//www.ebxml.org/msg-header-2_0.xsd">
    <eb:Manifest eb:version="2.0">
                  ...
    </eb:Manifest>
  </SOAP:Body>
</SOAP:Envelope>