applied patch from http://rdflib.net/issues/2007/02/23/bugs_in_rdflib.sparql.queryresult/issue
applied patch from http://rdflib.net/issues/2007/02/23/bugs_in_rdflib.sparql.queryresult/issue

git-svn-id: 60eb48102d1ca0c284ab3654bef916b01e1b221b@929 4f84a9ca-5c3e-0410-8a68-0bdf370325d5

nwebs/rdflib