A data session with a wireless device ordinarily cannot be initiated from the network side because the wireless device has no predetermined IP or other network address. Methods are disclosed for instead causing the wireless unit to initiate a data session with a target destination, thereby obviating the IP addressing problem. A voice call is first initiated by a requester application to a remote wireless unit. The requester transmits a request message to the remote wireless unit via the wireless voice channel using in-band techniques; preferably including a payload in the polling message that identifies the target destination. In response, the remote wireless unit initiates a packet data session with the target destination.