To summarize...
The link https://access.redhat.com/knowledge/solutions/306063
lists two issues
1. Files on NFS share are not getting displayed while executing ls
In the example there are 347 files on server file system and 3 on client.

In my case, I found one missing directory (not on client, but on server).
All files in troublesome directories and 2 of 3 subdirectories listed 3 times each. They are listed properly, one time each, on NFS server file system. 

2. On RHEL 6 NFS client, multiple . & .. entries getting listed when looking at them using ls? These direcories not there on NFS server:

Well, my NFS (SL6.1) client saw multiple entries, however, the entries actually exist on server file system.

So different. 

I can add from my notes, (I can't reboot to broken kernel today due to other's work), 
a) client side dmesg messages such as:
NFS: directory COMPILE_MATLAB/tsa contains a readdir loop.Please contact your server vendor. The file: ..�%
�������������������� has duplicate cookie 1816244270
NFS: directory matlabtools/pltwave contains a readdir loop.Please contact your server vendor. The file: getwordsAll.m has duplicate cookie 653075819

NFS: directory jr02_19/1 contains a readdir loop.Please contact your server vendor. The file: dmx.T007 has duplicate cookie 1805553535

b) boot of server (SL5.9) with broken kernel 2.6.18-348.1 showed RPC.idmap or idmapd (don't recall) with RED ERROR message. I don't remember seeing this when rebooting with older kernel that worked 2.6.18-308.24.1.el5.

Hope this helps for now,
Bill Lutter
> 

On 03/01/13, Akemi Yagi  wrote:
> On Fri, Mar 1, 2013 at 10:59 AM, William Lutter <[log in to unmask]> wrote:
> > I did not find this in archives, so a quick report. My apologies if I missed it.
> > NFS server SL5.9 with kernel 2.6.18-348.1.1.el5
> >
> > Problem: NFS client (SL6.1) would see multiple cookies for some files and directories. dmesg reported one directory in particular and a few files. All files in that directory repeated 3 times. 2 of 3 directories repeated 3 times. One directory missing on the NFS client side.
> >
> > Original file system fine. Directory listing correct. Older SL4.9 NFS client fine.
> >
> > Google search yielded:
> > https://bugzilla.redhat.com/show_bug.cgi?id=739222
> > which indicated a problem with this specific kernel (2.6.18-348.1) and that reverting to 2.6.18-308.24.1.el5 solved it.
> >
> > The reported problem was different than mine, it seemed to be specific to directories with a large number of files (160K), whereas, my directory had 167.
> >
> > Anyway, my NFS client problem solved by reverting to the next oldest kernel (2.6.18-308.24.1).
> >
> > What is the easiest way to track if updated kernels "fix" this issue other than trying them out.
> >
> > Bill Lutter
> 
> Can you check to see if your problem is related to this upstream KB article :
> 
> https://access.redhat.com/knowledge/solutions/306063
> 
> Akemi