I have an application that I need to integrate with the calendar. I can create vcalendars that create the appointment, but no matter what I have tried, I cannot get the vcalendar to set any category/color in the appointment. Even when I create the appointment in groupwise and send it external, I cannot see any category set. I have tried the VCALENDAR CATEGORIES tag but no success.

Is it possible to set the groupwise appointment category via VCALENDAR or similar so that different appointments can be shown as different categories?