1. A method, comprising:receiving an alert message at a client device from a communication system, the alert message indicating that a communication for the client device has been received at the communication system from a second client device;
opening a messaging application on the client device in response to the alert message;
connecting the client device to the communication system at an address included in the alert message; and
receiving the communication via the connection, wherein the address included in the alert message is the address of a communication server connected to the second client device that sent the communication to the communication system;
wherein the alert message is received when the client device is off-line from the communication system.