How to limit user to use a 6 digit password?


1- Is there a way to force the user to use a 6 digit password when they try to change their password through the *97 or *98 option?

2- If not, is there a way to turn-off password change totally?

3- If a hacker finds out the password to voic-email and calls into the system, presses *, what damage can they do other than deleting voic-email or listening to it? Can they somehow make calls at your cost for example?


Anything on this guys?