ldapsearch utf-8 results

Hello there I use a Debian 7.4 server with ldapsearch to search data about users on an Active Directory database. When a result of a search contains specials characters (such as é, è, à), no result is given, but if I delete special characters to the user profile, it works. How could I make it work with special caracters (guess it's a UTF-8 problem ?) ? Thanks in advance Nicolas -- signature -----