HTML Repr. Guide: Small ambiguity in regards to whitespace

Hi,

In section 2.16 White Spaces the guide states that white space characters must 
be preserved for content of <pre> <textarea> and elements with xml:space set 
to preserve. The following white space character is also listed: 

ASCII Form-feed (U+000C)

This character is not a valid XML character 
[http://www.w3.org/TR/REC-xml/#charsets], so it can't simply be preserved. 
It's not a valid XHTML character either [http://www.w3.org/TR/xhtml1/#C_15].

Maybe this issue should be addressed in the guide?

cheers,
asgeir