Quite a few have complained in the past that syncing their iPhone changes the time on their device. The error has been seen on both iCal and Outlook on a PC. And the fix lies in the TimeZone…Apparently the TimeZone on your system and the iPhone have to be the same! Simple. So check your iCal or PC to see if the Time Zone is the same as what you have set it on your iPhone. We may see an update to iPhone OS and/or iTunes to handle this a little more smartly in the future.
In iCal – go to PREFS/ADVANCED and make sure, ‘Turn on Time Zones Support’ is checked.
On the iPhone, – go to SETTINGS/GENERAL/DATE & TIME and make sure TIME ZONE SUPPORT = ON