Techniques to forward unsolicited messages from an (IS-2000) CDMA radio network via an HDR radio network to an access terminal. A session is first established between the access terminal and the HDR radio network. During session establishment or thereafter, the access terminal indicates to the HDR radio network an interest in receiving unsolicited messages from the CDMA radio network. The access terminal typically also registers with the CDMA radio network. Thereafter, unsolicited messages can be sent from a mobile station controller (MSC) to the HDR and CDMA radio networks, or sent from the MSC to the CDMA radio network, which then forwards the messages to the HDR radio network. The HDR radio network encapsulates the unsolicited messages and sends the encapsulated messages to the access terminal. The forwarding of unsolicited messages allows the CDMA radio network to communicate with an access terminal.