asterisk users - Apr 2005 - Controlling extentions through Management Interface (fwd)

Hi,

I was woundering if any of you knew how to control extentions/call groups,
etc through the console management interface in asterisk. (asterisk -r).

My problem right now is that the voice system is 500miles away and a moron
user setup something on a callgroup which tries to forward out a
non-existing line. (Basic call forwarding on incomming calls). Anyone have
any idea how i could either become the extention via the asterisk command
interface and then do the *73 or disable the user?

Also where does asterisk store its temporary configurations (live
configs)?

Please let me know
Thanks
Sascha