Stand by & Wake up

Question

Hi everybody,
I'm trying to make an application that sets the pc on stand by mode and after 10 seconds wakes up the system.
My problem is that the system doesn't wake up! I tried also on a hold P3 450 mhz with XP pro and there I even couldn't get stand by mode.
I've designed a simple form with a button, when the button is pressed the system should go in s.by and then wake up, the code I used is the following:

Set stand by mode:

Application.SetSuspendState(PowerState.Suspend, true, false);

Wake up the system after 10 secs, with relative Dll import:

        [DllImport("kernel32.dll")]
        public static extern IntPtr CreateWaitableTimer(IntPtr
        lpTimerAttributes, bool bManualReset, string lpTimerName);

        [DllImport("kernel32.dll")]
        public static extern bool SetWaitableTimer(IntPtr hTimer, [In] ref long
        pDueTime, int lPeriod, IntPtr pfnCompletionRoutine, IntPtr
        lpArgToCompletionRoutine, bool fResume);

        [DllImport("kernel32", SetLastError = true, ExactSpelling = true)]
        public static extern Int32 WaitForSingleObject(IntPtr handle, uint
        milliseconds);

static IntPtr handle;
public static void SetWaitForWakeUpTime()
{
      long duetime = -100000000; //-x0000000 = x sec
      handle = CreateWaitableTimer(IntPtr.Zero, true, "");
      SetWaitableTimer(handle, ref duetime, 0, IntPtr.Zero, IntPtr.Zero, true);
      handle = CreateWaitableTimer(IntPtr.Zero, true, "");
      SetWaitableTimer(handle, ref duetime, 0, IntPtr.Zero, IntPtr.Zero, true);
      uint INFINITE = 0xFFFFFFFF;
       int ret = WaitForSingleObject(handle, INFINITE);
}

Do you have any suggestion, thanks in advance

R.