This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
In Struts versions 1.2.8 and above you must specify cancellable="true" in your action mapping to enable the cancel button. In a normal action, you can simply call isCancelled(request) in order to determine whether the cancel button was pressed or not. If your action is a subclass of DispatchAction you must code a cancelled method in the Action class.