Finally disabled.
Try what Erel said and works fine. The event is no longer appearing.
Anyway, I also use checknotifications (it works on WM 5), and I guess there's nothing wrong. I mean, there are 18 events, (calupd.exe, calnot.exe, replog.exe, calendar.exe, TimeWizard.exe and clocknot.exe) some of them appearing two or three times, associated with different events (none, wakeup,time_change, restore_end, unknow and rs232_detected), but as I'm not quite sure what does they mean, and the problem is fixed, it's ok for me.
Thanks everyone.