Calendar upgrade for Treo 750 running Windows Mobile 5.0?

[steve911]

I've got a Treo 750 (supplied by my employer) running Windows Mobile 5.0 and we use Good messaging to sync handheld with the desktop Outlook (Inbox/Calendar/Notes, etc).

Calendar function on the treo is pretty basic - unlike the desktop, cannot show appoiints as anything other than busy (i.e. free/tentative/out of office), nor can the appointments be set for anything other than on the hour or 1/2 hour.

Anyone know of a plug-in or upgrade to add functionality while still allowing the device to sync with the server?

And switching to a Blackberry or something else is not an option - I have to make do with the 750 for now.

Thanks,
Steve