From: "JFC (Jefsey) Morfin" <jefsey(_at_)jefsey(_dot_)com>
RFC 3066 Bis imposes new constraints on the existing language tags
We need to be more careful in describing the proposed revision to RFC
3066 (aka RFC 3066 bis) wrt exiting libraries that conform to RFC 3066:
every tag valid under the terms of RFC 3066 bis will be recognized by an
existing library written to conform to RFC 3066. Not every tag that
*could* be recognized by such a library would be valid under RFC 3066
bis, but every tag actually valid today under RFC 3066 is also valid
under RFC 3066 bis.
The draft was written with careful attention to ensuring compatibility
with existing libraries written to support RFC 3066. The draft can be
said to impose new constraints that existing libraries would not impose;
I don't see how it could be said that the draft imposes new constraints
on those libraries.
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