void HandleUncaughtException(DebuggerEvent obj)
{
// FIXME: incomplete, not really reached here.
var uce = (ExceptionEventBody) obj.Body;
var e = new TargetEventArgs (TargetEventType.ExceptionThrown) {
Backtrace = this.ActiveThread.Backtrace,
IsStopEvent = true };
this.OnTargetEvent (e);
}