It appears that this has nothing to do with the call being international. I get the same with calling an 800 number....
The
voip.ms folk suggested I remove the leading '1' in my caller id I set in
voip.ms I did that without any change in the result.
The error message that is read out says the number you have called **118005551212 was not accepted by the service provider reason 491 - but the fact that it also reads back the **1 which I dialed to access SP1 (SP2 is my default) suggests that the entire set of digits might be going to
voip.ms and not just the 18005551212 part....
or this is an Obi message and t recites everything...?