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Setting the sender of a message

You can send a message from any of the SMS-enabled Tropo phone numbers attached to your application. When sending the message using the call or message APIs, set the callerId parameter to the number you wish to send from, just as you would do on a phone call.

Due to carrier restrictions, the message must come from one of the SMS-enabled phone numbers attached to your application. Spoofing the sender ID on a text message is not supported, and using a number other than one of your SMS-enabled numbers will result in the message being rejected by Tropo.