C2MS11 — Header UNIQUE-ID is Type "Header String"

UNIQUE-ID in the Header is of type Header String (to be Subject Token String due to C2MS11-49). According to table 8-3: "Globally unique ID – reserved for use by implementation (PSM)". Note that a "Header String" is limited to upper and lower alphanumeric plus '-' and '_'. Recommendation of C2MS is that best practice is to keep Header String to no more than 12 characters.

So, Header String or Subject Token String isn't the right type.

I think we need to know what GMSEC uses for a type of UNIQUE-ID. But, it possible, it would be good if it was a GUID, relating to C2MS11-16.