Major Appendix C.2 has three issues. First it writes:
"If SOAP 1.2 is used, instead of the SOAPAction header there will be an action parameter, as illustrated in the following listings"
This suggests that the action parameter is mandatory. However, BP 2.0, sections 3.7.4, 4.7.19 and 4.8 are clear that the action parameter is optional and is therefore not required to be present on the header.
Then it gives the following example:
Content-Type: Multipart/Related; boundary=MIME_boundary;
type=application/soap+xml;
start="<car-data@cars.example.com>"; action=leasing
According to BP 2.0 section 3.5.2, the value of the "action" attribute must be quoted. So better would be:
Content-Type: Multipart/Related; boundary=MIME_boundary;
type=application/soap+xml;
start="<car-data@cars.example.com>"; action="leasing"
But a third problem is that Multipart/Related does not have an action parameter. Better would be to use the start-info header:
Content-Type: Multipart/Related; boundary=MIME_boundary;
type=application/soap+xml;
start="<car-data@cars.example.com>";
start-info="application/soap+xml; action=\"leasing\""
Even better would be to state that the action parameter should not be used and, if present, may be ignored.