I have exhausted all other resources for trying to get the spell check function to work within Groupwise 6.5.6 when installed on Citrix Presentation Server 4.5.
Everything works fine with the exception of the spell checker, and some users are not happy without their spell checker.
1. Re-install the Citrix server.
2. During the Terminal Services portion of the setup, choose "Relaxed security".
The GroupWise spell checker should now work fine.
Disclaimer: As with everything else at Cool Solutions, this content is definitely not supported by Novell (so don't even think of calling Support if you try something and it blows up).
It was contributed by a community member and is published "as is." It seems to have worked for at least one person, and might work for you. But please be sure to test, test, test before you do anything drastic with it.