Weird:  	Content-type text/plain  according to tabulator for http://
www.w3.org/1999/02/22-rdf-syntax-ns but can't dupliacet it using curl even with 
exect header curl -I -H "text/xml,application/xml,application/xhtml+xml,text/
html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5,application/rdf+xml;q=1.2" 
http://www.w3.org/1999/02/22-rdf-syntax-ns

The text/plain causes the tabulator to offer to sho wa document view of it, 
which then gives a recursive invokation of tabulator extension, which doesn't 
make sense.