A method and medium are provided for changing operational parameters on a mobile device while the mobile device is roaming. The mobile device supplies data that indicates operational characteristics of the mobile device to a home network by sending a first short-message service (SMS) message to the home network. The mobile device is connected to a roaming network and thus, the first message is sent using the messaging services of the roaming network. The home network determines new operational parameters for the mobile device based on the data. The home network sends a second SMS message to the mobile device which delivered to the mobile device by the roaming network's messaging services. The mobile device receives the second SMS message at a designated control slot and changes stored operational parameters to the new operational parameters.