<?php class Services_Twilio_Rest_Calls extends Services_Twilio_ListResource { public static function isApplicationSid($value) { return strlen($value) == 34 && !(strpos($value, "AP") === false); } public function create($from, $to, $url, array $params = array()) { $params["To"] = $to; $params["From"] = $from; if (self::isApplicationSid($url)) { $params["ApplicationSid"] = $url; } else { $params["Url"] = $url; } return parent::_create($params); } }