attribute "aliasedObjectName" not supported in context

[Andrea Albert <andrea.albert@is.haw-hamburg.de>]

Hello to everybody,

I am running openldap-2.1.12 with BerkeleyDB.4.1.25 backend on a SuSE 
8.1 server to test it before putting up to production.
I am trying for some hours to implement an aliased object but I am 
getting everytime the same error message:
ldap_add: Object class violation (65)
        additional info: attribute "aliasedObjectName" not supported in 
context

and in /var/log/messages:

bdb_add: entry failed schema check: attribute "aliasedObjectName" not 
supported in context (65)

My ldif file is looking like:
dn: uid=telefon,ou=Mitarbeiter,dc=haw-hamburg,dc=de
objectClass: extensibleObject
objectClass: alias
aliasedObjectName: uid=telefon,ou=User,dc=haw-hamburg,dc=de

Has anyone any precious hints for me??

Thank you for your time

Andrea