Doubt in RT_SiteConfig.pm for LDAP overlay

Hi all,
I am using Dr. Riediger LDAP overlay code and have a problem accessing the
$RT::LDAPExternalAuth and $RT::LDAPExternalAut parameters set in the
RT_SiteConfig.pm. Has anyone used this overlay code for RT3.4.1 or higher?

I tried displaying the value of RT::LDAPExternalAut in the autohandler
program and it doesn’t display any value.I have checked the permissions in
all the overlay code too.Seems fine. Does anyone have any suggestions how
to go abt this?

My RT_SiteConfig.pm is the following:
$LDAPExternalAuth = 1; # will enable LDAP-Auth
$LDAPInternalAuthRequired = 1; # will require internal password
# in preference to LDAP-Auth
$LDAPExternalAuto = 1; # will create accounts “on the fly”
$LdapServer=“server.domain.com”; # LDAP server for authentication
$LdapCert= “”; # enables TLS, name is checked instead
# of the server name
$LdapCertDir= “”; # enables TLS, will check server name
# and certificate vs. CA chain from dir
$LdapUser=“CN=Nathan,OU=Users,OU=Information
Technology,OU=Departments,DC=domain,DC=com”;
$LdapPass=“password”; # password for binding
$LdapBase=“DC=domain,DC=com”;
$LdapUidAttr=“sAMAccountName”; # attribute for RT user name
$LdapFilter=“(objectclass=*)”; # additional filter
$LdapAuthFilter=“(status=A)”; # additional filter for authentication
only
$LdapMap = { # mapping LDAP attributes to RT3

‘RT user paramater’ => ‘LDAP entry’,

            'Name'                  => '$RT::LdapUidAtt',
            'EmailAddress'          => 'mail',
            'RealName'              => 'cn',
       };

Regards,
Ahalya