A method of handling buffered media data in a data session for a Push-to-Talk-over-Cellular, PoC, Push-to-Talk, PTT, based service of a wireless communications system having at least one Push-to, PT, client and a Push-to, PT, server, wherein the PT client is comprised within a terminal and wherein the terminal comprises a buffer for storing buffered media data, characterized in that the method comprises: receiving, by the PT client, a control message from the PT server, wherein the control message is a Talk-Burst revoke message; checking, by the PT client, at least one reason code field included in the control message, wherein the reason code field has different values that depend upon different reasons, wherein the different values allow the PT client to consider whether to discard remaining buffered media data or to transmit remaining buffered media data to the PT server; and selectively processing, by the PT client, the remaining buffered media data based on the checked reason code field, wherein the control message is received via the data session for the PoC PTT based service that is established between the PT client and the PT server, and wherein the PT client and the PT server support Session Initiated Protocol, SIP, techniques, wherein the selectively processing step comprises: transmitting, by the PT client, the remaining buffered media data to the PT server, if the reason for the reason code field indicates that a user of the PT client has talked too long or indicates that the talk burst is pre-empted, and discarding, by the PT client, the remaining buffered media data, if the reason for the reason code field indicates that only one user is in the data session, or indicates that the PT client does not have permission to send the talk burst. receiving, by the PT client, a control message from the PT server, wherein the control message is a Talk-Burst revoke message; checking, by the PT client, at least one reason code field included in the control message, wherein the reason code field has different values that depend upon different reasons, wherein the different values allow the PT client to consider whether to discard remaining buffered media data or to transmit remaining buffered media data to the PT server; and selectively processing, by the PT client, the remaining buffered media data based on the checked reason code field, wherein the control message is received via the data session for the PoC PTT based service that is established between the PT client and the PT server, and wherein the PT client and the PT server support Session Initiated Protocol, SIP, techniques, wherein the selectively processing step comprises: transmitting, by the PT client, the remaining buffered media data to the PT server, if the reason for the reason code field indicates that a user of the PT client has talked too long or indicates that the talk burst is pre-empted, and discarding, by the PT client, the remaining buffered media data, if the reason for the reason code field indicates that only one user is in the data session, or indicates that the PT client does not have permission to send the talk burst. transmitting, by the PT client, the remaining buffered media data to the PT server, if the reason for the reason code field indicates that a user of the PT client has talked too long or indicates that the talk burst is pre-empted, and discarding, by the PT client, the remaining buffered media data, if the reason for the reason code field indicates that only one user is in the data session, or indicates that the PT client does not have permission to send the talk burst.