samba - Jun 1998 - SmbClient Kills NT 4 in conjunction w/ Amanda (Revisited)

Ok.. I've tried tweaking several settings on Samba (1.9.18p4) in order to
try to keep it
from killing several machines that get backed up weekly via Amanda (using
smbclient).
What always appears to happen is that for one reason or another, Samba is
booking
along copying files and then all of a sudden NT stops communication and
smbclient ends
up hanging forever (regardless of the keepalive setting).  Now, at this
point, the NT
client is completely DOA and IF you were to look at the network neighborhood
on that
machine (assumed you were still logged in), you would see ONLY that machine!

Now, I've heard from other users (at least one) that this has been seen at
other
establishments and I believe on other platforms (non Solaris).. I would like
to find a fix
for this, and I don't need someone bitching at me claiming it is a problem
with NT (Yes,
I did have someone e-mail me saying that).  The bottom line is that this IS
a problem,
and somehow I would like to solve it.  Now, we have two machines that
exhibit the
problem and both are running NT 4 SP3 (I believe the other is running SP3).
I currently
do NOT have a complete log of the activities of one of these sessions, but
will attach
one at the next failure.

We are currently doing full disk backups (less any of the standard locked NT
O.S. files)
for 8 machines and typically it kills one or more of the machines each week
(my machine
is usually the first to go).  I'm upgrading Samba to 1.9.18p7 tomorrow
morning in the
vain hope that my problems may be reduced, but am reluctant to make any
assumptions
yet.

Server Background :
    Sparc Ultra Enterprise 450 (Quad 300Mhz CPU)
    Solaris 2.6
    100Mb Ethernet (hme0)
    Samba 1.9.18p4
    Amanda 2.4.0-980222

Client Background :
    Windows NT 4.0 SP2 and/or SP3


Samba Configuration File :

;======================= Global Settings
====================================[global]

  debuglevel     = 3
  workgroup      = dh
  comment        = Justice Samba Server
  admin users    = root
  log file       = /usr/local/samba/var/log.%m
  username map   = /usr/local/samba/lib/users.map
  max log size   = 50
  hide dot files = yes
  browseable     = yes
  preserve case  = yes
  short preserve case = yes
  guest account  = guest
  encrypt passwords = yes
  status         = yes
  dead time      = 60
  keep alive     = 60
  oplocks        = false

  lock directory = /usr/local/samba/var/locks
  locking        = yes
  domain master  = no
  local master   = yes
  preferred master = yes
  os level       = 65
  share modes    = yes
  wins support   = no
  wins server    = nnn.nnn.nnn.nnn
  socket options = IPTOS_LOWDELAY TCP_NODELAY SO_SNDBUF=16384
SO_RCVBUF=16384
  security = user

  load printers  = no
  printing       = sysv
  print command  = /usr/ucb/lpr -r -P%p %s
  printcap name  = /bin/lpstat
  lpq command    = /usr/ucb/lpq -P%p
  lprm command   = /usr/ucb/lprm -P%p %j