aspnetdb- Add users to role via stored procedure executed against the database NOT from inside asp.net's roles.AddUserToRole

How can I add users to a specified application and role by using one of aspnetdb's stored procedures instead of using Roles.AddUserToRole from inside an ASP.NET app?

 

I have a list of users to add and I want to do it with TSQL from the SQL Server management studio, not ASP.

 Thanks!
...