OK this works.
My mistake, the concerned character is in fact a Windows character (CP1252)
I hadn't noticed when I converted my schema to a text file.
De : Hallvard Breien Furuseth [mailto:email@example.com]
Envoyé : lundi 20 octobre 2008 19:39
À : Emmanuel Duru
Cc : openldap-its(a)OpenLDAP.org
Objet : RE: (ITS#5755) Schema file not always converted to LDIF and
The problem is the 8-bit Latin-1 character in the certificate's DESC.
It works if you convert the schema file to UTF-8.
Slapd should have refused to start with a non-UTF-8 attribute DESC.
Possibly that should wait for OpenLDAP 2.5 though, and just log a
warning for now.