a customer of our company has buy two host packages. with the same contact name, say, Jack. Although he has a usename and password respectively., when he use a usename and password log into the control panel, simultaneously, he can switch to another control panel of host. He want to do that every host can not switch to each other,because his two packages are used among different group,maybe his own customers. So I desire to wonder how to achieve it? my sincere thanks go to you in advanced.