rockdrummer, while I'd love to say that qwerty is wrong, there is evidence that blocking the 389 port does not prevent the VP-100 from connecting to the directory. Whether it's still an LDAP server or not, we don't know. Your VP-100 manual was most likely one of a million printed and inserted into your VP a long time ago and given to you as part of their backlog of inventory. So, your manual isn't the latest info, and Sorenson hasn't bothered to update the manual because they're getting the VP-200 out eventually. So why bother to update an expensive document that's going to be phased out anyway?
You're right, though, there's nothing that qwerty says that can be verified on the internet. There's no such thing as CORE out there. Most likely it's just his wording for a custom database directory that he thinks Sorenson made. I've not seen any evidence, BEYOND the blockage of port 389 not being enough to prevent connection to Sorenson's LDAP servers, that states that LDAP is no longer being used.