undefined attributetype

[Helke Schröder <toepper@zentaur.de>]

hi,
I've got a problem trying to add new entries with own attribute.

in the slapd.conf I have insert:
    include /etc/openldap/schema/schema.schema
(schema check is on)

and this schema.schema looks like this:
    #ldxPcUserDn
    attributetype( 2.16.840.1.113719.2.177.4.64.1 NAME 'ldxPcUserDn'
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
     MULTI-VALUE )

    #ldxPcAdd
    objectclass( 2.16.840.1.113719.2.177.6.64.1 NAME 'ldxPcAdd'
     SUP top
     AUXILIARY
     MAY 'ldxPcUserDn' )

and my entry.ldif is:
    dn: ou=tt,o=ldx,c=de
    objectclass: organizationalUnit
    objectclass: top
    objectclass: ldxPcAdd
    ou: tt
    ldxPcUserDn: blabla

and then I get:

    [root@localhost hilke]# /usr/local/bin/ldapadd -f entry.ldif -x -D
    "cn=Manager,o=ldx,c=DE" -w secret
    adding new entry "ou=tt,o=ldx,c=de"
    ldap_add: Undefined attribute type
            additional info: attribute type undefined

        ldif_record() = 17

Adding this entry without the attribute (but with objectclass: ldxPcAdd)
there is no problem
What did I wrong?

Thanks
Helke