Upgrading from 6.5.3 to 8.5 - compatibility issues?

We have a 6.5.2 server and have had the go ahead to upgrade to 8.5 - are there any known issues with NSF files runnign under 8.5 i.e. compatibility etc? Will everything still work ok?

Just wanted to check from the community rather thyan the salesman!

Many thanks

Subject: hierarchical names in names.nsf

Dear Duncan,

There is one issue we had to deal with which is that under 7, 8 and 8.5 you need to have hierarchical names implemented in your user IDs and names.nsf. Otherwise it should be pretty straight forward.

Ekkehard