Hello,
I have just implemented extension module for LDAP authentication and it does work.
However I think that it is also necessary to provide some synchronization between LDAP and Konakart users database.
Do I think correctly?
Yes, probably... once you've authenticated your user in your LDAP system you can either register or update (if present already) that user in KonaKart. There are APIs available to support these kinds of operations...