Import to GroupWise Calendar

I need to be able to automatically update a user or users GroupWise Calander from other Programs (Confluence ,ICAL).And Vice Versa. If someone can just point me in the right direction that would be much appreciated.

I'm on GroupWise ver 8.0 with the latest hotfix.

I would like user calendars to mesh with the Office calendar's and the Users group Calanders...
All User's in the office are in a group there are like 5 or 6 groups.

Also when a user add's something to lets say a confluence or Ical calendar which will be the Office Calendar all the user's GroupWise calendars are updated with the appt. eg a meeting for everone in the office.
Or a user updates a group calendar which will be an ICAl or Confluence Calendar that the user's in said group's groupWise calendars are updated.