[libxml++] problem with utf8 xml file parsing ('Glib::ConvertError')

[Nicolas <nico picapo net>]

Hello!

I tried to parse utf8 .xml files with the sample program 
example/sax_parser/ (i've tried with both 2.20 and 2.23 versions). The 
program crash during the execution at the position of the first utf8 
char with the  following message : "terminate called after throwing an 
instance of 'Glib::ConvertError'
20 Abandon (core dumped)"

for exemple here is the result output for the parsing of 
http://packs.shtooka.net/chi-balm-hsk1/ogg/index.xml
-------------
on_start_document()
node name=index
on_characters():

node name=group
  Attribute swac_lang = chi
  Attribute swac_speak_name = Wei Gao
  Attribute swac_speak_gender = M
  Attribute swac_speak_birth_year = 1979
  Attribute swac_speak_lang = chi
  Attribute swac_speak_lang_country = CH
  Attribute swac_speak_lang_region = Pekin
  Attribute swac_speak_liv_country = CH
  Attribute swac_speak_liv_town = Pekin
  Attribute swac_pron_speed = 1
  Attribute swac_coll_name = Base Audio Libre de Mots Chinois
  Attribute swac_coll_section = HSK 1
  Attribute swac_coll_desc =
terminate called after throwing an instance of 'Glib::ConvertError'
Abandon (core dumped)
                                  
(There is a the following content header at the begining of the xml file 
: <?xml version="1.0" encoding="UTF-8"?>)

What could I do to solve the problem?
Regards,
Nicolas