Sent view has emails with FUTURE Date

There are emails in the sent item with future date (october 2011). We have checked system date-time, notes.ini setting and all looks in place.

This is not affecting all emails in the sent view but many of them have been sent with wrong date

Please advise what could have caused it and how to troubleshoot

Server mailfile also same as local.

Subject: system date/time changed then …

users often open their windows date/time widget to check a date, they will move the date ahead or back then don’t cancel the change. They do some work with the changed date then the computer does a time sync with a server on your domain and resets it back to the correct date/time.