OpenLDAP Behaviour with Sudo

Hey all

I've recently been playing with OpenLDAP in some dev VMs and just wanted to check that the behaviour I'm seeing is normal.

I've setup a basic LDAP server in Ubuntu server 12.04 and created an LDAP user account and group. I've added the LDAP group to the sudoers file but when I login as my LDAP user and run a command as Sudo, I'm prompted for the credentials of the local admin account I created with the server.

I was expecting to just have to type in the LDAP users password to run something as sudo but perhaps I've missed something here, It's not a major issue really. I know you can add a sudo schema and have sudoers directly in LDAP but I read somewhere this does not work with TLS? Can anyone confirm/deny this?

I'm totally new to OpenLDAP so apologies if this is a stupid question. Any advice is always welcome!