spell checker in french

Hi,

Squirrel mail : 1.4.9a
os: debian 3.1
php : 4.3.10-18
apache : 1.3.33
in config.php :
$squirrelmail_default_language = 'fr_FR';
$default_charset = 'iso-8859-1';
$lossy_encoding = false;

i enabled the plugin : html_mail in which i forced the using of the
spellchecker aspell with french dictionarie

i also put
$aspell_opts = "-a --lang=$lang --encoding=iso-8859-1 -H";
instead of
$aspell_opts = "-a --lang=$lang --encoding=utf-8 -H";
in
fckeditor/editor/dialog/fck_spellerpages/spellerpages/server-scripts/spellchecker.php
It works but only with words without 'accent'.
Exemple : i put : maiso de mon frère => it prompts : maiso frÃ de mon
frère (so he adds "frÃ" )
making no sense to the phrase

Does someone have a solution about that?
Thanks