Hi Paul,
this is how _I_ understand slunicode:
"." always matches a single byte, because the string functions (below) also
work with arbitrary binary data.
• find
• match
• gmatch
• gsub
from slunicode have different category classes
(http://www.unicode.org/Public/4.0-Update1/UCD-4.0.1.html#General_Category_Values)
So you should use %a or something to match a whole utf8 encoded item. Or you
can use unicode.utf8.sub(str,n,n) to get the nth utf8 character.
So I'd consider this correct behavior, but I have had some discussion on this
before where I am pretty alone with my opinion... :)
http://tug.org/pipermail/luatex/2010-March/thread.html#1242
Patrick