Outlook 2007: How to determine if you are the owner of an Appointment

There doesn't appear to be an easy way to find out if the current user is the owner of an Appointment. Maybe I've something extremely simple, but I just couldn't find that property called IsOwner.

I basically want to prevent functionality from being available if the user has opened an Appointment that isn't in one of their own calendars (ie: readonly and from someone elses calendar). After looking through the AppointmentItem and MAPIFolder properties, I finally found something that was useful: MAPIFolder.Store. This property returns a Store object except when the Folder is a shared folder (ie: someone elses). Cool.

So, I've now created my IsOwner method:

    public static bool IsOwner(AppointmentItem anAppointment)
{
    bool result = false;

    if (anAppointment.Parent is MAPIFolder)
    {
        //
        // A Store of null indicates a shared folder (ie: not the current user's).
        //
        result = (((MAPIFolder)anAppointment.Parent).Store != null);
    }

    return result;
}

This, of course, makes the assumption that if the AppointmentItem is not in a shared folder, it is in a folder that is owner by the current user. I'll need to confirm this, but for now it allows me to move forward.