Problem adding olcModuleLoad

[Daniel Jung]

running 2.4.39

# module{0}, config
dn: cn=module{0},cn=config
objectClass: olcModuleList
cn: module{0}
olcModuleLoad: {0}syncprov.la
olcModuleLoad: {1}auditlog.la

ldif:
dn: cn=module{0},cn=config
changetype: modify
add: olcModuleLoad
olcModuleLoad: memberof

using ldapmodify
modifying entry "cn=module{0},cn=config"
ldap_modify: Other (e.g., implementation specific) error (80)
        additional info: <olcModuleLoad> handler exited with 1

What am i missing here?

Thanks