[css3-syntax] Null bytes and U+0000

Hi,

CSS 2.1 mentions in §4.1.3:

 > It is undefined in CSS 2.1 what happens if a style sheet does
 > contain a character with Unicode codepoint zero.

However, U+0000 is not mentioned at all in css3-syntax (apart from being 
non-printable.) I think that css3-syntax as it stands requires 
implementation to handle U+0000 like any other code point.

Can this be problematic for implementations where the null byte is a 
string terminator? Should we allow them to use U+FFFD REPLACEMENT 
CHARACTER instead, where they should have U+0000 but can not? For 
example for a zero hexadecimal escape: \0

-- 
Simon Sapin