On Java platform, when the application tries to send a SMS the API returns 1, indicating that it was not possible (because the application does not have permission to do so). But I believe the proper scenario should be that a notificaiton popup appears asking the user if he/she accpets sending of the SMS or not.
Sending SMS is an important feature for us.
If we define 3 priority levels: A, B and C (A being highest priority) I would classify this A.
Regards
Dennis @ Bloo