Bug#452837: mounting unionfs via nfs fails

[Martin Stechert <Martin.Stechert@online.ms>]

Package: unionfs-modules-2.6.18-5-486
Version: 2.6.18+1.4+debian-7+etch3

mounting a unionfs filesystem via nfs fails with permission denied.
The individual directories that are part of the union can be mounted without 
problems.
Running rpc.mountd with "debug=all" gives no additional info.

client mount command
==================
mount 192.168.1.13:/data /mnt/
mount.nfs: 192.168.1.13:/data failed, reason given by server: Permission 
denied

/etc/fstab
=======
none            /data           unionfs dirs=/data1:/data2  0       5

/etc/exports
=========
/data           192.168.1.1/24(ro,sync,subtree_check)
/data1          192.168.1.1/24(ro,sync,subtree_check)
/data2          192.168.1.1/24(ro,sync,subtree_check)

/var/log/syslog
============
Nov 25 16:15:45 Marvin mountd[3654]: MNT3(/data) called
Nov 25 16:15:45 Marvin mountd[3654]: authenticated mount request from 
DesasterArea.home.net:817 for /data (/data)