It doesn't need Bindery, nor can it use it anyway (Bindery and IPX are not the same). Technically GroupWise doesn't need IP either, but without it you won't get Internet mail. Using IPX (via mapped drive) is also not recommended, although that is your current configuration. I'm guessing that right now, the GroupWise system is used for internal communication and calendaring only. I also doubt you could even install GroupWise 7 on NetWare 4.1. I believe NW5.1 is the minimum version.
With your NetWare and GroupWise being so old, you're looking at doing a Migration no matter what you do. My personal preference would be to migrate to a newer NetWare server and utilize GroupWise 7. That way you retain all NDS accounts. The BIGGEST bonus would be that your existing GroupWise data would stay intact and you wouldn't have to extract it. You would also have a much more secure system, with less overhead on system resources.
I understand that this may not be an option for you, even a NetWare to NetWare migration will be a challenge for you if you are not familiar with how it works. Also you can't upgrade from 4.1 straight to 7.0. I believe you first have to upgrade to 5.5, then go to 7.
All that being said, you should look at the Novell Open Workgroup Suite. It includes everything you need to make this happen, and again, you can even install GroupWise on Windows if you want. GroupWise is cross platform and works on Linux, Windows, and NetWare.
Here are the minimum requirements for GroupWise 7:
Marvin Huffaker, MCNE
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