How to remove (or change) a user ID

During the evaluation of RTC, I want to change the naming convention for the user IDs (from <firstname><lastname> to <loginid>). Two ways come to mind:
- remove the existing user ids and create new ones (without garbage of the old)
- change the existing user ids
Neither of these options I know how. Can you help?
Thanks,
Frank.
- remove the existing user ids and create new ones (without garbage of the old)
- change the existing user ids
Neither of these options I know how. Can you help?
Thanks,
Frank.