Non-ASCII letters trigger "Lexical error"

Entering e.g.
é {}
in direct input mode at
http://jigsaw.w3.org/css-validator/#validate_by_input
results in the error message
Parse Error Lexical error at line 1, column 1. Encountered: "?" (63), after 
: ""

As far as I can see, "é" conforms to CSS identifier syntax and should be 
accepted. If rejected, it should not be rejected as if a question mark "?" 
had been entered.

I have tested various combinations, and it seems as if the W3C CSS Validator 
does not accept non-Ascii letters in identifiers in general. I suspect this 
is a recent problem. People have probably used the validator on stylesheets 
with such identifiers, but I have not seen complaints about the issue until 
very recently (and cannot find anything relevant to this in the archives - 
searched with the word "lexical").

Yucca