Re: Fw: [idn] IDNs in email message bodies

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

> > Encoded-words are designed for parts of the headers that
> > are strictly for human consumption, not the machine-readable parts.
> 
> Yeah, should have read "2047-encoding" <ascii@ACE-encoding>
> 
> The point is still the same, ACE-encoding/decoding can occur at the same
> time as 2047-encoding/decoding, when the display data is converted into
> protocol data.

there are two problems with this statement.

the first is that address processing is done at many different places,
not all of which are concerned with presentation.  an SMTP server might
need to do ACE decoding on addresses independently of any user agent.

the second is that in many current implementations rfc 2047 is done at the 
wrong time - a message is RFC 2047 headers is often "converted" to 
use raw characters at some point prior to presentation, and those
raw characters often leak out in replies, forwarded messages, etc.

I'd agree that if a user agent were implemented properly, it would decode
rfc 2047 and ace domain names *for the purpose of presentation* at the 
same time - but this might not be the same time that rfc 2047 is decoded
by a current implementation of that user agent.

Keith