Automount problem 4.0F and Linux 2.6

Hello SysAdmins - 
  I'm having a strange problem with automount and Linux NFS servers,
kernel 2.6.x and higher.  On a DU 4.0F system, patchkit 6, I can
manually issue a mount command and things are ok, but trying to access
the same filesystem via /net/host through automount doesn't work.

As far as I can tell, automount mounts to linux servers that do work
(kernel 2.4 vintage) show the same arguments in mount -l as the manual
mounts that work for the 2.6 kernels (2.6.9, 2.6.18, 2.6.23)

I don't see anything in the logs on the alpha for the automount
failures.  On the linux side, I see messages for the successful manual
mounts, but not the automount failures.

I'm assuming the problem is the way Linux NFS has changed, but I've had
no luck tracking that down, so I thought I'd try here.  I find it odd
that it works manually but not via automount.

Would it be useful to add -T to my automount args on the Alpha?

Many thanks,
Eric



Some info from the Alpha:
AUTOMOUNT_ARGS="-M /.automount /net -hosts"

# mount -v newlinux:/myfs /tmp/newlinux
newlinux on /tmp/newlinux type nfs (v3, rw, udp, hard, intr)

# mount -l
newlinux:/myfs on /tmp/newlinux type nfs (v3, rw, exec, suid, dev,
nosync, noquota, grpid, atimes, udp, hard, intr,
ac, cto, wsize=8192, rsize=8192, timeo=11, retrans=4, maxtimo=20,
acregmin=3, acregmax=60, 
acdirmin=30, acdirmax=60)

# umount /tmp/newlinux

# cd /net/newlinux/myfs
/net/newlinux/myfs: No such file or directory.

# cd /net/oldlinux/myfs
# pwd
/.automount/net/oldlinux/myfs

# mount -l | grep oldlinux
oldlinux:/myfs on /.automount/net/oldlinux/myfs type nfs (v3, rw, exec,
suid, dev, nosync, noquota, grpid, atimes, 
udp, hard, intr, ac, cto, wsize=8192, rsize=8192, timeo=11, retrans=4,
maxtimo=20, acregmin=3, acregmax=60, 
acdirmin=30, acdirmax=60)

Some info from the Linux systems:
Working system:
# uname -a
Linux oldlinux 2.4.27 #2 Tue Aug 10 15:37:09 EDT 2004 i686 athlon i386
GNU/Linux

Non-working system:
# uname -a
Linux newlinux 2.6.23.1-42.fc8 #1 SMP Tue Oct 30 13:55:12 EDT 2007 i686
i686 i386 GNU/Linux