NFS automount not happening

[Ross Boylan <RossBoylan@stanfordalumni.org>]

I have a diskless workstation running testing, and although
its /etc/fstab is
/dev/nfs	 /		 nfs defaults 0 0
none		 /tmp		 tmpfs defaults 0 0
none		 /var/run	 tmpfs defaults 0 0
none		 /var/lock	 tmpfs defaults 0 0
none		 /var/tmp	 tmpfs defaults 0 0
none		 /media		 tmpfs defaults 0 0
192.168.40.2:/usr/local	 /mnt/usr/local	nfs defaults 0 0
192.168.40.2:/usr/local/var/media	 /usr/local/var/media	nfs defaults 0 0

The root fs is mounted correctly (during the boot sequence, before it
gets to fstab), but the other 2 NFS filesystems are not.  I can mount
them manually once the system is up.

Can anyone suggest why the NFS automount is not working, or what to do
about it?

I have a theory that the mounts are supposed to happen when the network
device comes up; the regular network up routines are not triggered to
avoid screwing up the root fs.  /etc/network/interfaces has

# The primary network interface
# do not bring up interface twice--PXE already did it
#allow-hotplug eth0
iface eth0 inet dhcp

Is my theory correct?

Thanks.
Ross Boylan