Hi.
I am running Mysql 4.0.17 but I think it will work also under 3.23.xx. I'll check it and let you know.
I used the following phpdig_words_chars variable
$phpdig_words_chars['iso-8859-7'] = '[:alnum:]ÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÓÔÕÖ×ØÙ¢¸¹º¼¾¿ÚÛáâãä æçèéêëì*îïðñóôõö÷øùÜÝÞßüýþúûÀ*';
The link is
http://find.pin.gr/search.php