Angel L. Mateo writes:
I find it difficult to think is a client problem, because we are having the problem with at least three different client software (postfix 2.3.8, courier-imap 3.0.8 and freeradius 1.1.3). The errors are provocating that users are being not found in the clients, and I know that with our previous ldap versions there isn't any problem because we don't have "user not found" errors in the clients.
Could be quite unrelated. For example, did you just point the new LDAP server at the data written by the old server? I don't know if the database formats are compatible. It might help to slapcat the old database to an LDIF file (preferably using the old OpenLDAP version), move away the database files, and slapadd them back with the new OpenLDAP version.