Patent ID: 7047007

Claim:
A method of automatically re-establishing a GPRS connection between a mobile station and a network in which the network for the mobile station has changed from a first network to a second network following a cell reselection procedure, the method comprising: in the mobile station: receiving a detach request from a first network to terminate a current GPRS connection between the mobile station and the first network; terminating the GPRS connection between the mobile station and the first network pursuant to the received detach request; determining if the detach type parameter associated with the detach request is set to re-attach not required; determining if the detach cause parameter associated with the detach request contains a null value, when the detach type parameter associated with the detach request is set to re-attach not required; determining if either the MCC or MNC of the second network is different from the first network and whether the second network supports GPRS in the present cell, when the detach cause parameter associated with the detach request does contain a null value; and automatically initiating a GPRS attachment with the second network in the present cell, when either the MCC or MNC of the second network is different from the first network and the second network supports GPRS in the present cell.