A communication session is established between a first communication device and a second communication device. The communication session comprises a first dialog between an application server and the first communication device. The first communication device uses a first network address in the first dialog. In response to an event, such as a first network interface failing, a SIP INVITE with replaces header message is received by the application server with a second address of the first communication device. In response to receiving the SIP INVITE with replaces header message from the first communication device with a second address of the first communication device, the first dialog between the application server and the first device is reestablished using the second network address.