Hook for Input Panel/Mouse Windows CE

I develop an application for Windows CE 5.0 Device and actually I need just to observe if the user makes no inputs (over Input Panel or mouse click) for more than “X” minutes on the application. In this case the user will be logout from the application.
Usually in this case I install a hook (SetWindowsHookEx) for keyboard and mouse and … all fine. But this seems to not work on Windows CE 5.0. The hook works of course on the normal .Net, also on the mobile emulations, but it doesn’t work on the Windows CE 5.0 device (SetWindowsHookEx - fails). Some people say that SetWindowsHookEx doesn’t work on Windows CE, but I never found such an affirmation on Microsoft sites. Is it something special I need to consider in this case?
Maybe I’m on the wrong way, but know somebody any solution for my purpose? I guess I’m not the first developer which needs to intercept inputs over Input Panel / Mouse on Windows CE. It is an WindowsForm Application with many Forms.
For any idea thank you in advance! I develop in C# but also in C++ is no problem to understand.

Best Regards,
Emil

If all fail you can use a timer instead. With each tip on that panel you make just an reset of it.