[CentOS] Sendmail using LDAP authentication problem

Hi , all ;

My openldap is running fine . Sendmail configuration is done. I want to use LDAP authentication only. User of my mailserver should not have a Linux users .

I am running CentOS 5.3 i386 . Openldap-2.3.43-3.el5 , sendmail-8.13.8-2.el5

All the software is already installed and running . LDAP has the following tree: uid=xxx, ou=People, dc=test, dc=com

I want to know what I've to change which configuration file and any pointer to the doc with clearly says the configuration .

Any help will be appreciated. Please I am kind of stuck and waiting for anyone who can clear this cloud.

Thank you in advance ~