incomplete description of "Text" content set

The description of the Text content set given in 
http://www.w3.org/TR/2004/WD-xhtml2-20040722/mod-text.html is "abbr | 
cite | code | dfn | em | kbd | l | quote | samp | span | strong | var". 
  The sub and sup elements are missing from this definition, although 
they appear to be included in the RELAX NG implementation.

--Maxwell Terpstra