can't query on a known principal name.
$ set LD_LIBRARY_PATH=/opt/shibboleth-sp/lib; export LD_LIBRARY_PATH
-$ /opt/shibboleth/bin/shibtest -h test-handle \
+$ /opt/shibboleth-sp/bin/shibtest -h test-handle \
-f urn:mace:shibboleth:test:nameIdentifier \
-q https://idp.example.org/shibboleth