[Serusers] Changing Dialed Number.

Hello List. I have succesfully installed SER on my Linux platform. I'm authenticating users and authorizing calls through the RADIUS SER support. What i want to do know is change the dialed number by a user. For this task i would like to know if i can use the same RADIUS system for authorize a call. For example, i make a call, the Radius message goes to my Radius Server, the Radius server adds a parameter called Re-Direct-Number=1234567, this parameter is taken by the SER and inserted in the R-URI parameter in the SIP message?. Is possible to do this? If is not possible, can i use the exec() command to do something like that? I would appreciate any help. Thanks in advance Best Regards Ricardo Martinez