You can only have one ratebook per trunk.
If your local, national and international is for example
Telkom rates (there exist a ratebook for it) and your
cellular calls is handle vir routers (has a different
rate than that Telkom in this example and does not overflow
to Telkom), you can setup a custom ratebook with Telkom
as base only changing the costing for you cellular calls
as per service provider.
Note that for each prefix it can only handle one rate
per trunk.
See tng custom rate configuration and format
OR
Log into TNG as admin, go to Home Page, select SETUP CUSTOM RATES.
Click on 'Setup new ratebook' and then the ? icon. It will list
a document explaining how to setup custom rates.