One work around . You could install NWClient without using it to log to the tree. Check the box “Workstation only”, by this way you could log to Windows domain and not to the tree. You could also have Netware dependancies needed by the OCX.
One another. Dedicated a station (or the server) to hold a netware client. Install GW and create an applet whitch synchronyse information needed between NDS and Groupwise.
Not sure it could help you, but sometime ‘exotic’ solution works