We are using a hosted MS Exchange provider, and they claim that our account can only have one administrator. They also claim that they cannot change which login is granted administrator privileges. This means that the user account that was initially created five years ago is the only account that can change our billing information, among other things.

The employee associated with the current admin account is no longer with the company, so we'd like to move the admin privileges to a new "sysadmin" account, and delete this employee's account. Shouldn't this be really easy to do? Is my hosted exchange provider telling the truth?