RE: Registration of some code pages

[Shawn Steele <Shawn.Steele@microsoft.com>]

Out of curiosity, is anyone aware of differences between 31J and windows' implementation?

-----Original Message-----
From: Masatoshi Kimura [mailto:VYV03354@nifty.ne.jp] 
Sent: Wednesday, September 08, 2010 4:57 AM
To: Ned Freed
Cc: Anne van Kesteren; NARUSE, Yui; Shawn Steele; 'ietf-charsets@iana.org'
Subject: Re: Registration of some code pages

(2010/09/08 8:01), Ned Freed wrote:
> So, unless there are cases where a code point has been used in 
> conflicting ways, why don't we just add the additional characters to 
> shift_jis and iso-2022-jp? (Perhaps a revision to RFC 1468 is in
> order.)

Because it is not enough to add the characters.
Some Windows-31J characters have incompatible Unicode mappings with corresponding Shift_JIS characters.
The most notable example is wave dash. (Shift_JIS 0x8160.) Although this character supposed to correspond to U+301C, Windows-31J converts 0x8160 to U+FF5E FULLWIDTH TILDE.
Some existing implementations will be likely to be broken if the mappings are changed.

I wonder why your customers didn't tell this fact.
--
VYV03354@nifty.ne.jp