Calendar sync problem

I sync with Outlook 2003 and this has always worked fine with my Palm Treo 750 (WM5.1). I now also have an HTC Diamond Touch (WM 6.1) which also works fine except - "All day events" in my outlook calendar show up one day early in my diamond calendar. All other appointments show correctly - just all day or multi-day are wrong. The same events show on the correct day on the Treo.
This also applies to the standard Microsoft calendar days in Outlook, e.g. St Patricks Day is the 17th March on Outlook and Treo but 16th on Diamond. However my dental appointment on the 17th from 1200 to 1230 shows correctly everywhere.
Any ideas???

Im not trying to teach you to suck eggs, but have you checked your regional settings on the problem device,in the past i have come across this problem quite a lot when people forget to change the locale to English(United Kingdom) as default is English(United States), if it isnt this im sorry,just a thought!

There is a patch for outlook that fixes some time zone issues (e.g. the problems on all-day events). Sorry i forgot the exact name of that patch but you can try search on M$ website.