code: function processJsonpUrl( requestSettings ) {
  		if ( requestSettings.type.toUpperCase() === "GET" ) {
  			if ( !CALLBACK_REGEX.test( requestSettings.url ) ) {
  				requestSettings.url += (/\?/.test( requestSettings.url ) ? "&" : "?") +
  					(requestSettings.jsonp || "callback") + "=?";
  			}
  		} else if ( !requestSettings.data || !CALLBACK_REGEX.test(requestSettings.data) ) {
  			requestSettings.data = (requestSettings.data ? requestSettings.data + "&" : "") + (requestSettings.jsonp || "callback") + "=?";
  		}
  	}
docs: Append the required callback parameter to the end of the request URL, for a JSONP request