problem in open ldap in centos

Hi I am trying to use open ldap in centos.
I have installed all the packaged.

When I try to use slappasswd to encrypt the password, it does nothing.
I searched for the file and I found out that it is in /usr/sbin and that the file is link to slapd.
However slapd doesn't encrypt anything.

How can I solve this.

Thanks in advance.