DXD = Direct eXtension Dial, and is a function of the Automated Attendant. "If you know your party's extension, you may dial it now."
DID = Direct Inward Dial, which is what you are referring to when you ask if people can call directly to an extension. And yes, the Partner ACS can do that. Are you able to do that with your old Partner II?
PMV = typo of PVM (Partner Voice Messaging)
