slapd crashes when the attribute manager, with an empty value, is inserted (ITS#1843)

[ue000001@guest.telecomitalia.it]

Full_Name: Matteo Bonavita
Version: 2.0.23
OS: Solaris 2.8, FreeBSD 4.5-STABLE
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (213.26.132.205)


Scenario:
OpenLdap Master - Replica
The manager attribute is indexed (eq) only on the replica.

ldapmodify is issued. The input ldif files look like:

dn: uid=myuid, o=myorg
changetype: modify
replace: manager
manager: 

or

dn: uid=myuid, o=myorg
changetype: modify
add: manager
manager: 

The operation is allowed on the master but the slapd on the replica, when
synchronized, crashes.
This does not happen if the manager attribute is not indexed.

I applied the patch referenced by ITS#1662 and this solves the problem from
client
side. That is, ldapmodify where is applied the patch does not allow the
processing
the above ldif files.

Additional info: slapd seems to crash (debbugging it) when
the ldbm_cache_open is called.