Problem in saving an unicode literal in a sparql store

example.py

#! /usr/bin/env python
# -*- coding: utf-8 -*-

import rdflib
import urllib
import traceback
from rdflib.namespace import FOAF, RDF
from rdflib.plugins.stores.sparqlstore import SPARQLUpdateStore

def save(graph, name):
    try:
        agent = rdflib.URIRef('http://example.com/resource/1')
        graph.add((agent, RDF.type, FOAF.Agent))
        graph.add((agent, FOAF.name, rdflib.Literal(name)))
    except:
        print "\n====== Can't save " + repr(name) + " ======\n"
        traceback.print_exc()

def main():
    store = SPARQLUpdateStore(
                queryEndpoint = "http://<host>/openrdf-sesame/repositories/<repository>",
                update_endpoint = "http://<host>/openrdf-sesame/repositories/<repository>/statements",
                context_aware = False)
    graph = rdflib.Graph(store)
    
    save(graph, 'Raphaël Troncy')
    save(graph, u'Raphaël Troncy')

if __name__ == '__main__':
    main()

output

====== Can't save 'Rapha\xc3\xabl Troncy' ======

Traceback (most recent call last):
  File "./example.py", line 14, in save
    graph.add((agent, FOAF.name, rdflib.Literal(name)))
  File "/usr/lib/python2.7/site-packages/rdflib/graph.py", line 397, in add
    self.__store.add((s, p, o), self, quoted=False)
  File "/usr/lib/python2.7/site-packages/rdflib/plugins/stores/sparqlstore.py", line 571, in add
    r = self._do_update(q)
  File "/usr/lib/python2.7/site-packages/rdflib/plugins/stores/sparqlstore.py", line 631, in _do_update
    update = urllib.urlencode({'update': update})
  File "/usr/lib64/python2.7/urllib.py", line 1312, in urlencode
    v = quote_plus(str(v))
UnicodeEncodeError: 'ascii' codec can't encode character u'\xeb' in position 85: ordinal not in range(128)

====== Can't save u'Rapha\xebl Troncy' ======

Traceback (most recent call last):
  File "./example.py", line 14, in save
    graph.add((agent, FOAF.name, rdflib.Literal(name)))
  File "/usr/lib/python2.7/site-packages/rdflib/graph.py", line 397, in add
    self.__store.add((s, p, o), self, quoted=False)
  File "/usr/lib/python2.7/site-packages/rdflib/plugins/stores/sparqlstore.py", line 571, in add
    r = self._do_update(q)
  File "/usr/lib/python2.7/site-packages/rdflib/plugins/stores/sparqlstore.py", line 631, in _do_update
    update = urllib.urlencode({'update': update})
  File "/usr/lib64/python2.7/urllib.py", line 1312, in urlencode
    v = quote_plus(str(v))
UnicodeEncodeError: 'ascii' codec can't encode character u'\xeb' in position 85: ordinal not in range(128)