You have the option to block certain call numbers (e.g. charged hotlines such as 0900) with the following call route:
For the calling number, specify a registered client to restrict the rule to those calls made by the corresponding user.
By setting the source line to "User.#", "User.ISDN", "User.SIP" or "User.Analog", you have the option of restricting the rule to the corresponding subscriber, irrespective of the telephone number they are using.
