Bizarre error while initializing a DIT

[Maykel Moya <moya-lists@infomed.sld.cu>]

I'm trying to initialize a DIT. This is the error I get:

root@tpro:/var/lib/ldap# slapadd -v -n 2 -l tproca1st.ldif 
PROXIED attributeDescription "DC" inserted.
hdb_monitor_db_open: monitoring disabled; configure monitor database to
enable
slapadd: dn="DC=tpro,DC=ca" (line=1): (64) naming attribute 'DC' is
obsolete

root@tpro:/var/lib/ldap# cat tproca1st.ldif 
dn: dc=tpro,dc=ca
objectClass: top
objectClass: dcObject
objectClass: organization
o: My test Orga
dc: tpro

root@tpro:/var/lib/ldap# slapcat -b cn=config
...
dn: olcDatabase={2}hdb,cn=config
objectClass: olcDatabaseConfig
objectClass: olcHdbConfig
olcDatabase: {2}hdb
olcSuffix: DC=tpro,DC=ca
olcLastMod: TRUE
olcMaxDerefDepth: 15
olcReadOnly: FALSE
olcMonitoring: TRUE
olcDbDirectory: /var/lib/ldap/tproca
olcDbCacheSize: 1000
olcDbCheckpoint: 512 30
olcDbConfig: {0}set_cachesize 0 4194304 0
olcDbConfig: {1}set_lk_max_objects 1500
olcDbConfig: {2}set_lk_max_locks 1500
olcDbConfig: {3}set_lk_max_lockers 1500
olcDbNoSync: FALSE
olcDbDirtyRead: FALSE
olcDbIDLcacheSize: 0
olcDbLinearIndex: FALSE
olcDbMode: 384
olcDbSearchStack: 16
olcDbShmKey: 0
olcDbCacheFree: 1
olcDbDNcacheSize: 0
structuralObjectClass: olcHdbConfig
entryUUID: 140c5ffc-f953-102c-9659-bb5cef3694ca
creatorsName: cn=config
createTimestamp: 20080808050326Z
olcDbIndex: objectClass eq
olcDbIndex: mail eq
olcAccess: {0}to dn.subtree="ou=users,dc=tpro,dc=ca"
filter="(objectClass=sldM
 ailRecipient)" attrs=mail,sldMailbox,userPassword by
dn="cn=dovecot,dc=tpro,dc=ca" read by * break
olcAccess: {1}to attrs=entry,uid,objectClass by
dn.base="cn=dn-search,dc=tpro,dc=ca" read by * break
olcAccess: {2}to attrs=userPassword,shadowLastChange  by
dn.base="cn=admin,dc=
 tpro,dc=ca" write  by anonymous auth  by self write  by * none
olcAccess: {3}to dn.base=""  by * read
olcAccess: {4}to *  by dn.base="cn=admin,dc=tpro,dc=ca" write  by * read
entryCSN: 20080818145521.939111Z#000000#000#000000
modifiersName: cn=admin,DC=tpro,DC=ca
modifyTimestamp: 20080820145521Z

I'm using Ubuntu package for slapd 2.4.11.

Any hints?

Regards,
maykel