The Ribbit API, and all the REST libraries, require you to submit phone numbers in RFC3966 format. This requires that the Ribbit US sales number (619) 916-2565 is submitted to the API as tel:16199162565
It's not always straightforward to validate phone numbers easily, ensuring that the country code is included. With the help of Javascript, we can make this a lot easier.
You may have seen our Google Wave gadget that uses our Javascript library to create an outbound conference call to lots of people in a Google Wave. You really don't need to write a lot code to accomplish this.