HTC has just released an official update for both the HTC HD2 and the HTC Touch2 Windows Phone 6.5 devices and it is related to Daylight Saving Time.
Without going into many details, the manufacturer describes the update for both devices in few words. It is supposed to “readjusts your clock to account for the hour gained during Daylight Savings”. In order to apply, download the proper EXE file for you handset, copy it to your device and apply. Since this is a software patch, you will need to reapply after a Hard Reset or a ROM upgrade.