SVN objects to checking in these files due to some property of the .xml
file type it assumes. So first check them in via
    svn add --force *
then force proper attributes:
    svn propset --force svn:mime-type application/xml *.xml
    svn propset --force svn:eol-style native *.xml
and in the xhtml/ subdirectory:
    cd xhtml
    svn propset svn:mime-type text/html *.html
    svn propset svn:mime-type text/plain *.css *.xsl Makefile *.rb
    svn propset svn:mime-type image/jpeg *.jpg
    svn propset svn:mime-type image/gif *.gif
    svn propset svn:eol-style native *.html *.css *.xsl Makefile *.rb