1 hour time shift

I know this has been asked a million times already, but I don't see my exact
situation.
I have a brand new computer with Vista operating system, and running Outlook
2007.
Ever since the shift to Daylight Savings time, SOME (not all) of the
appointments that are made by others on my calendar show up an hour early.

I've checked the time settings on my Windows clock (it made the jump to DST
without my intervention) and the time settings in Outlook. Everything seems
to be fine.
Any ideas on what is causing this problem for only some items?