NW 6.0 sp4, or SP3 BM3.7 Current sp

When using the Netware client 4.83 there is no problem but if you use
The client 4.90 or 4.90sp1a you can not map a drive or access the file
system on any volume on the BM3.7 server

Remove the 4.90 client and install 4.83 client then its ok

I have a netware 6.5 server and BM3.8 at another site and the 4.90
client works ok

This problem can be reproduced at multiple sites where this combination

Any one have any ideas on how to fix this problem