way off topic but, for example,  

change
ls lang_*.xml | sed -e "s@\(.*xml\)@<language>\1</language>@" > list.xml
to
echo "<x>" > list.xml
ls lang_*.xml | sed -e "s@\(.*xml\)@<language>\1</language>@" >> list.xml
echo "</x>" >> list.xml

(someone's going to say do it in perl instead:-)

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