Hello,

Thanks to all for your answers !

Finally, thanks to an article dealing about Xelatex, bibtex files and utf-8
problem (see
http://skalldan.wordpress.com/2011/08/01/%E3%82%A4%E3%83%B3%E3%83%89%E5%AD%A6%E4%BB%8F%E6%95%99%E5%AD%A6%E3%81%AB%E3%81%8A%E3%81%91%E3%82%8B-utf-8-%E3%81%AB%E3%82%88%E3%82%8B-tex-%E6%96%87%E6%9B%B8%E4%BD%9C%E6%88%90-4/)
I got the idea how to solve my problem.

In the bib file I have surrounded all japanese words by {\jpn }, like in
this minimal example :
%%%%%%%%%beginning of the example%%%%%%%%%%%
@article{uzawa2011tpp,
author = "Hirofumi Uzawa {\jpn 宇沢弘文}, Uchihashi Katsuto {\jpn 内橋克人}",
journal = "Sekai {\jpn 世界}",
title = "Taidan TPP wa shakaiteki kyôtsû shihon wo hakai suru
{\jpn 対談TPPは社会的共通資本を破壊する}",
year = 2011,
month = "april",
publisher = "Iwanami shoten {\jpn 岩波書店}",
pages = "62-72",
url = "http://ci.nii.ac.jp/naid/40018706510/",
note = "test"
}
%%%%%%%%%%%%end of file%%%%%%%%%%%%%%

Then, thanks to the documentation for simplefonts I have introduced a
typeface definition, like in this minimal example :

%%%%%%%%%%beginning of file%%%%%%%%%%%%%
\usemodule[simplefonts]
\setmainfont[Arno Pro]
\definesimplefonttypeface[jpn][hiraginokakugothicpro]
\enableregime[utf8]

\setupbibtex[database=biblio]

\starttext
test
\completepublications[criterium=all]
{\jpn 知らない  金 11月 25, 2011  10:21午後}
\stoptext

%%%%%%%%%%end of file%%%%%%%%%%%%%%%

And everything works well when compiling the whole with "context *tex".

The only question remaining in my mind is : is there another way ? Just out
of curiosity, since Hans Hagen mentioned "Thomas" who use greek.


2011/11/25 Hans Hagen <pragma@wxs.nl>

> On 25-11-2011 20:03, Christian wrote:
>
>  Same here. It messes up when converting .bib to .bbl. Maybe check your
>> bbl file, too. Mine looks like this, for example:
>> a={{Hirofumi Uzawa~宇沢弘文}}
>>
>> You could try to write the .bbl file directly yourself, although that is
>> not a comfortable option, if you have many Japanese entries.
>> Apart from that there's not much coming to mind.
>>
>
> It makes me wonder how Thomas gets his greek etc done in bibtex.
>
> Hans
>
>
> ------------------------------**------------------------------**-----
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