samba - Oct 2006 - Problems with samba on RHEL4 (was ok on RHEL3)

Hello,

We have a RedHat3 server, with some NFS mounts to Solaris9 servers.
That works nicely.  We also run samba on top of that, for Windows
access to the NFS shares.  Works fine.

However, on a RedHat4 system, using the exact same mount, we
experience odd behavior.  I can access the shares through samba,
see all the files, but when I double click on a file to open it, I get a
long long hang.  Eventually (2-5 minutes later) the file will open.

My mount looks like

mount -t nfs  -o soft,intr,rsize=1024,wsize=1024,nosuid,udp
mysolariserver:/opt/path /misc/path

SMB.CONF:
[my_docs]
comment = My Docs
path = /my_docs
create mask = 0000
directory mask = 0000
force create mode = 0775
force directory mode = 0775
browseable = no
guest ok = no
read only = no
locking = no
blocking locks = no
oplocks = no
level2 oplocks = no
posix locking = no
strict locking = no

Same results using autofs vs command line mount.  I have tried playing with
the rsize/wsize, seems to have no effect.  Also, I have tried removing
the udp option, same result.

RedHat3 system that works...
samba-3.0.9-1.3E.10
autofs-4.1.3-186
nfs-utils-1.0.6-44EL

RedHat4 system that hangs...
samba-3.0.10-1.4E.9
autofs-4.1.3-187
nfs-utils-lib-1.0.6-3
nfs-utils-1.0.6-70.EL4


Looking at a snoop of the traffic between the servers shows that the
RedHat4 system seems to get hung up in a loop with about two minutes
of this:

myredhat4server -> mysolaris9server          PORTMAP C GETPORT
prog=100021 (NLM) vers=4 proto=UDP
        mysolaris9server -> myredhat4server PORTMAP R GETPORT port=0
myredhat4server -> cs8          PORTMAP C GETPORT prog=100021 (NLM)
vers=4 proto=UDP
        mysolaris9server -> myredhat4server PORTMAP R GETPORT port=0

Where as on the RedHat3 snoop, I never see any of that PORTMAP traffic?

Any idea where I should look?

Thanks
Shane