Just reading about Fiberlink Communication's Maas360 (
http://fiberlink.com).
Have you heard of them/tried this?
From what I'm reading, they support not only centralized administration of this kind of authentication information, but also centralized distribution of system patches, AV definitions, DLP and Encryption software, etc. They push security policies down to the end points, and have dashboard reporting of software inventory on the end points and other information.
Any help appreciated.
Thanks,
Sam