Finally Microsoft have released an update for NAV that allows it to use WSS3.0 for Employee Portal instead of WSS2.0. This has been much requested and looked forward too, especially in our office were we are doing more and more work involving WSS3 and MOSS.
If you are a MBS partner you can download the update here https://mbs.microsoft.com/partnersource/downloads/releases/EmployeePortalNAV50.htm
