Re: [EAI] UTF-8 in Message-IDs

"Charles Lindsey" <chl@clerew.man.ac.uk> Mon, 15 August 2011 09:17 UTC

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From: "Charles Lindsey" <chl@clerew.man.ac.uk>
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Subject: Re: [EAI] UTF-8 in Message-IDs
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On Sat, 13 Aug 2011 23:08:48 +0100, <ned+ima@mrochek.com> wrote:

>> And the "EAI experiment" phase did not test this plan,
>> there's no evidence I'm aware of that UTF-8 in Message-
>> IDs is harmless.
>
> I'm sure it is not, just as utf-8 in addresses is far from harmless and  
> is
> going to require all sorts of infrastructure changes.
>
> But I fail to see how this is in any way relevant. We're defining a new  
> message
> format here that *cannot* be downgraded to the old format and retain all
> semantics. This is true irrespective of how message-ids are handled. As  
> such,
> utf-8 in message-ids is a small additional cost.

Yes, but you have to consider all the other protocols using mail-like  
formats and their use of the Message-ID. For exmaple, if EAI were to be  
carried over into Netnews (quite a likely development) it would NOT be  
regarded as a "new message format" since the transport paths for Netnews  
are already 8-bit clean and it would simply be necessary for those who  
wish to take advantage of the new facilities to ensure that their user  
agents were suitably upgraded. There will never be a need for  
"downgrading" except at gateways back into the email system.

But within Netnews the Message-ID plays a crucial role, so it is  
reasonable to ask whether UTF-8 in it would cause problems. According to  
the current standards it would not be allowed, of course, but in practice  
the transport paths might or might not barf. So the question has to be  
asked (and I do not know the answer off the top of my head).

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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