From: "Phillip H. Griffin" <asn1(_at_)mindspring(_dot_)com>
In all of the following OBJECT IDENTIFIER values, US is invalid
since it does not begin with a lowercase letter. Same for S in
SMIMECapabilities.
2.8 Receipt Request Syntax
receiptRequest OBJECT IDENTIFIER ::=
{iso(1) member-body(2) US(840) rsadsi(113549) pkcs(1) pkcs-9(9)
SMIMECapabilities(15) 3}
I think a little common sense is required when interpreting capitalization
conventions. Can you cite a reference that REQUIRES the initial letter
of OID arcs to be lower case? And if you want to change US to uS, I think
you'll have to petition ISO, not the S/MIME working group - country codes
were defined long ago in a forum far far away.
It is helpful to have a convention that distinguishes between structure
element names (initial lower) and the syntax definitions they refer to
(initial upper). But as far as I know, there is no ASN.1 module which
defines a syntax associated with any of the iso or joint country codes,
thus there is no danger of confusion or collision between name and
syntax.