XML declaration in SOAP?

Hello,

 

I have a question regarding xml declaration in soap message:

- is xml declaration mandatory for soap message?

 

The SOAP 1.1 spec states that SOAP message is encoded using XML. 

The XML 1.0 spec defines that XML document SHOULD begin with an XML
declaration.

This is also approved in EBNF grammatics:

document    ::=         prolog  element  Misc*

prolog      ::=         XMLDecl? Misc* (doctypedecl  Misc*)?

 

On the other hand, the xml declaration line is absent in all examples of
soap message in the specification.

 

In our case it can be a compatibility issue. Can you please help me to
interpret the specification right way?

 

Thank you in advance.

 

Best regards

Roman Vinogradov

MERA, Russia