ldap_bind: Invalid credentials (49)

[John Espiro <john_espiro@yahoo.com>]

System:
Ubuntu 10.10 server 64bit
@(#) $OpenLDAP: slapd 2.4.23 (Nov 19 2010 17:41:28) $
buildd@allspice:/build/buildd/openldap-2.4.23/debian/build/servers/slapd

Problem:
I am following the guide here:
http://blog.suretecsystems.com/archives/163-OpenLDAP-Quick-Tips-Change-loglevels-on-the-fly!.html

Entering:
    ldapmodify -x -D 'cn=config' -W -f log.ldif

Gives me:
    Enter LDAP Password:
    ldap_bind: Invalid credentials (49)

I enter the password (that is also stored in ldap.secret), but the error
persists.

I've got to be missing something obvious, but it's not clear what that is...

John