[idn] Requirement [12] and charset tagging

[Paul Hoffman / IMC <phoffman@imc.org>]

>[12] This document does not recommend any charset for IDN. If more than
>one charset is used, or might be used in future, in the protocol, then
>the protocol must specify all the charsets being used and for what
>purpose. It must also conform to [RFC1766] by tagging the charset. No
>implicit rules should be allowed for multiple charsets. A CCS(s) chosen
>must at least cover the range of characters as currently defined (and as
>being added) by ISO 10646/Unicode.

The sentence "It must also conform to [RFC1766] by tagging the 
charset." is overkill for a protocol that only allows one charset. 
For example, if the protocol only allows UTF-8, why should every name 
part have to be marked as UTF-8? I propose changing that sentence to 
"If multiple charsets are allowed, each item must be tagged with the 
name of the charset".

--Paul Hoffman, Director
--Internet Mail Consortium