Techniques for use by a mobile device configured to operate in a wireless network for the communication of data messages with a server are described. When the mobile device does not have an open session with the server, the mobile device receives from a service node via the wireless network a message which informs the mobile device that a data message has arrived at the server and needs to be retrieved. The message includes an identifier which identifies the data message at the server. In response to opening an application at the mobile device, the mobile device communicates directly with the server via the wireless network for retrieving the data message. This involves commencing an open session with the server, sending to the server a command for retrieving the data message, and receiving from the server the data message in response to sending the command. The mobile device may use the identifier for retrieving the data message from the server.