In Groupwise 8.0.2 Help it says,
"Sharing an Existing Calendar with Other Users

1. Right-click the calendar you want to share.
2. Click Sharing.
3. Click Shared with.
4. In the Name field, start typing the name of a user, or click the
Address Book button to select the user from the Address Selector dialog
5. When the user’s name appears in the field, click Add User to move
the user into the Share list.
6. Click the user’s name in the Share list.
7. Select the access options you want for the user.
8. Repeat Step 4 through Step 7 for each user you want to share the
folder with.
9. Click OK"

My client pointed out that there is no sharing option. That this help
isn't helpful. Just saying ...

Next time I'm over there I'll show her how to do this through Tools/