Re: [idn] An experiment with UTF-8 domain names

[Keith Moore <moore@cs.utk.edu>]

> Am I right in thinking that UTF-8 style IDNs are used then Boris and
> Ivan can't communicate unless Ivan can persuade his ISP to upgrade his
> sendmail, but an ACE would only need Ivan to upgrade his mail client ?

probably so.  the chance is good that a UTF-8 return address will
either be mangled or be unusuable for some other reason.

> In fact if Boris starts the exchange and although it would look odd,
> wouldn't Ivan be able to just hit `Reply' on his existing email client ?

probably so.  though if experience with RFC 2047 is any guide, there is 
some chance that some MTA or gateway will prematurely "decode" the IDN
and and thereby make it unusable.  we could try to write the specifications
clearly enough that this wouldn't happen very often.  but people 
often mis-implement much more subtle things than this.

Keith