Try this:
- do not make changes with /lib/misc.lib.php as above, restore to original file
- edit /lib/western_chars.php, add above characters into appropriate latin characters
$western_chars['a'] = array('*','À','á','Á','â','Â','ã','Ã','Ä' ,'ä','å','Å','æ','Æ');
$western_chars['i'] = array('ì','Ì','*','Í','î','Î','Ï','ï');
$western_chars['u'] = array('ù','Ù','ú','Ú','û','Û','Ü','ü');
$western_chars['e'] = array('è','È','é','É','ê','Ê','Ë','ë');
$western_chars['o'] = array('ò','Ò','ó','Ó','ô','Ô','õ','Õ','Ö' ,'ö','œ','Œ','ø','Ø');
$western_chars['y'] = array('ý','Ý','Ÿ','ÿ');
$western_chars['n'] = array('ñ','Ñ');
$western_chars['d'] = array('ð','Ð');
$western_chars['c'] = array('ç','Ç');