ispconfig sites --> IP address * and x.x.x.x how to block

[ngoyette]

Hello

i am trying ispconfig because we have some client in our small company "me and the boss" , and we have come upon 2 question...

First one is we made couple of client , and one of them went and modified the IP-address from * to x.x.x.x (x.x.x.x being our real server ip address) and any request made to the server pointed to his site...
How can we block our user from changing this or can we LOCK then to * ?


Second one is we have 1 customer needing fetchmail to get email from old account,,, this work alright , but how can we decide the fetch sequence? like if we want to fetch every 5 minutes ? how can we do this for 1 client?


thank you!