I never heard anything constructive with regards to the permission problems in knfsd other than, "yea I reported this two years ago and it's still broke" from other people who were similarly afflicted. But I also have a problem with the userland nfsd under 2.2.15. Under 2.0.x, when an NFS server went away briefly, such as during a reboot, NFS clients frequently wouldn't recover and I'd end up having to reboot them (although sometimes I could get away with remounting the affected file systems). Under 2.2.x this behavior largely dissappeared until 2.2.15. In 2.2.15, this old problem has resurfaced with a vengence. If an NFS server goes away it is almost guaranteed I'll have to reboot the NFS clients now. I don't know what changed from 2.2.14 but this is a real PITA.