in the Page_Load event of the content pages remove the attached eventHandler if there is any, register new eventHandler to the specified event of the controls.
in the content page :
protected void Page_Load(object sender, EventArgs e)
{
WebControlType myControl = (WebControlType) Master.FindControl("WebControlID");
// Removes the Handler
myControl.SpecifiedEvent -= theDefaultEventHandler;
myControl.SpecifiedEvent += new EventHandler(myControl_SpecifiedEvent);
}
protected void myControl_SpecifiedEvent(object sender, EventArgs e)
{
// Implementation goes here
}