NFS exporting is supported on kernels versions >= 2.6.0. For 2.4.X kernels the exporting infrastructure is not refined enough, so don't expect this to work. You need to add an fsid=NNN option to /etc/exports to make exporting a FUSE directory work. You may get ESTALE (Stale NFS file handle) errors with this. This is because the current FUSE kernel API and the userspace library cannot handle a situation where the kernel forgets about an inode which is still referenced by the remote NFS client. This problem will be addressed in a later version.