Byte order marks and character sets

[Robert Burbidge <robert.burbidge@poptel.coop>]

I find the current state of documentation regarding character sets and byte
order marks somewhat unsatisfactory. 

1. Page 5 of current draft says "EPP use with current character sets other
than UTF-8 is not described in the document". Is this meant to imply that
the current draft assumes UTF-8 for all XML document interchange? If so it
would be preferable to say so in explicit terms rather than the double
negative at present.

2. Byte order marks are only considered in passing on page 76 in reference
to RFC3023. This RFC is relevant and useful if an underlying transport uses
MIME headers for passing EPP documents around. However, I don't think it
offers any useful advice fo transports that don't have a MIME type or
similar - such as the current TCP binding specification. Our EPP server
interprets incoming BOMs if the client provides them, and if no BOM is
provided UTF-8 encoding is assumed. But when we generate responses, should
we provide the UTF-8 BOM or not? In an ideal world all clients would have a
conforming XML parser and it would not matter for UTF8 data. However, having
seen some of the published EPP clients it looks like no one handles BOM
correctly for server responses. [Note: if you have written a client that
does handle BOM correctly please accept my apologies!]

3. TCP bindings section 5 "does not introduce or present any
internationalization or localization issues". If we don't make the BOM
situation explicit then we absolutely will be introducing long term i18n
issues for unicode (etc.) contact or domain names.

This may also have some bearing on the current discussions surrounding
international postal addresses, although this is not my field of expertise
... I'll leave it for others to consider.

Rob Burbidge