[relax-ng] Encoding declaration, MIME type

At the last telcon, we discussed the possibility of not having any encoding 
declaration; the compact syntax would be defined on a sequence of Unicode 
characters rather than on a sequence of bytes.  However, "include" and 
"externalRef" seem to me to present a problem for this approach.  They take 
URIs as arguments and dereferencing a URI gives me a entity containing a 
sequence of bytes.  It seems to me we need to define how an implementation 
should dereference a URI so as to get a sequence of Unicode characters. 
Thinking about this I was unclear what MIME type a RELAX NG schema in 
compact syntax should be sent as.  Would it be text/something or 
application/something? Murata-san, any thoughts on this?

James