> BO3-IMP-4: Some Printers would return all printer attributes even when
> one unsupported attribute was requested. The Printers recognized this
> an implementation problem.
On the other hand,
"A response MAY contain attribute groups, attributes, attribute syntaxes,
values, and status codes that the client does not expect. Therefore, a
client implementation MUST gracefully handle such responses and not refuse
to inter-operate with a conforming Printer that is returning IETF standards
track extension or vendor extensions, including attribute groups,
attributes, attribute syntaxes, attribute values, status codes, and
out-of-band attribute values that conform to Section 6.
I don't see how a client can distinguish these extra values from
extensions, so it should ignore them. So this is also a client