[CentOS] CentOS samba MS Word corruption

We're using CentOS samba for about 20 workstations, mostly XP, some 2000 and 
two win98. Samba shares a data directory with Word, Excel and Access 
documents/db's. Also Exact for Dos is running from this share (executable and 
data).

The users experience a long delay every morning opening the first Word 
document (Word 97, Word 2000). This could take 10 minutes or so. If they 
close Windows before the document is loaded and open it later on the document 
is corrupted. If they go for a cup of coffee in the meantime everything is 
fine. After the first document the rest of them reportedly has no problems 
(allthough I doubt this).

Excel, Access and Explorer have no problems !

This is the global section of the smb.conf:
---------
[global]
        log file = /var/log/samba/%m.log
        load printers = yes
        idmap gid = 16777216-33554431
        socket options = TCP_NODELAY SO_SNDBUF=8192 SO_RCVBUF=8192
        wins server = 192.168.9.5
        interfaces = 192.168.9.0/255.255.255.0
        username map = /etc/samba/smbusers
        winbind use default domain = no
        template shell = /bin/false
        dns proxy = no
        cups options = raw
        netbios name = server02
        server string = Samba Server
        idmap uid = 16777216-33554431
        path = /tmp
        workgroup = WORKGROUP
        os level = 20
        printcap name = /etc/printcap
        security = user
        preferred master = no
        max log size = 50
--------
Samba is running as a workgroup server, no domain integration or fancy stuff.
There is still an older Windows 2000 server running as Wins server which is to 
be replaced by the CentOS server.

I find these entries (below) in /var/log/messages which point to locking 
problems. By Googling I found reports from people who think the stock samba 
release RedHAt is broken with repect to locking and advice to upgrade to 
latest version.

I would love to here your experiences and thoughts on this cause this gives me 
the creeps as you can imagine.

Thanks in advance

Paul
============
Mar 13 11:42:29 server02 smbd[10062]: [2007/03/13 11:42:29, 0] 
smbd/oplock.c:oplock_break(839)
Mar 13 11:42:29 server02 smbd[10062]:   oplock_break: receive_smb timed out 
after 30 seconds.
Mar 13 11:42:29 server02 smbd[10062]:   oplock_break failed for file 
Apps/EXACT70/USR/BEDRYF (dev = fd01, inode = 541383, file_id = 74).
Mar 13 11:42:29 server02 smbd[10062]: [2007/03/13 11:42:29, 0] 
smbd/oplock.c:oplock_break(911)
Mar 13 11:42:29 server02 smbd[10062]:   oplock_break: client failure in oplock 
break in file Apps/EXACT70/USR/BEDRYF
Mar 13 11:42:59 server02 smbd[10062]: [2007/03/13 11:42:59, 0] 
smbd/oplock.c:oplock_break(839)
Mar 13 11:42:59 server02 smbd[10062]:   oplock_break: receive_smb timed out 
after 30 seconds.
Mar 13 11:42:59 server02 smbd[10062]:   oplock_break failed for file 
Apps/EXACT70/USR/BEDRYF.IX (dev = fd01, inode = 541384, file_id = 75).
Mar 13 11:42:59 server02 smbd[10062]: [2007/03/13 11:42:59, 0] 
smbd/oplock.c:oplock_break(911)
Mar 13 11:42:59 server02 smbd[10062]:   oplock_break: client failure in oplock 
break in file Apps/EXACT70/USR/BEDRYF.IX
Mar 13 11:43:10 server02 smbd[9113]: [2007/03/13 11:43:10, 0] 
smbd/oplock.c:request_oplock_break(1055)
Mar 13 11:43:10 server02 smbd[9113]:   request_oplock_break: no response 
received to oplock break request to pid 10062 on port 33112 for dev =
 fd01, inode = 28264408, file_id = 68
Mar 13 11:43:10 server02 smbd[9113]: [2007/03/13 11:43:10, 0] 
smbd/open.c:open_mode_check(734)
Mar 13 11:43:10 server02 smbd[9113]:   open_mode_check: exlusive oplock left 
by process 10062 after break ! For file Apps/EXACT70/EMENU.INI, d
ev = fd01, inode = 28264408. Deleting it to continue...
Mar 13 11:43:10 server02 smbd[9113]: [2007/03/13 11:43:10, 0] 
smbd/open.c:open_mode_check(738)
Mar 13 11:43:10 server02 smbd[9113]:   open_mode_check: Existent process 10062 
left active oplock.
Mar 13 11:43:19 server02 smbd[9136]: [2007/03/13 11:43:19, 0] 
smbd/oplock.c:request_oplock_break(1055)
Mar 13 11:43:19 server02 smbd[9136]:   request_oplock_break: no response 
received to oplock break request to pid 10062 on port 33112 for dev =
 fd01, inode = 541384, file_id = 75
Mar 13 11:43:29 server02 smbd[10062]: [2007/03/13 11:43:29, 0] 
smbd/oplock.c:oplock_break(839)
Mar 13 11:43:29 server02 smbd[10062]:   oplock_break: receive_smb timed out 
after 30 seconds.
Mar 13 11:43:29 server02 smbd[10062]:   oplock_break failed for file 
Apps/EXACT70/EMENU.INI (dev = fd01, inode = 28264408, file_id = 68).
Mar 13 11:43:29 server02 smbd[10062]: [2007/03/13 11:43:29, 0] 
smbd/oplock.c:oplock_break(911)
Mar 13 11:43:29 server02 smbd[10062]:   oplock_break: client failure in oplock 
break in file Apps/EXACT70/EMENU.INI
Mar 13 11:43:51 server02 smbd[9136]: [2007/03/13 11:43:51, 0] 
smbd/oplock.c:request_oplock_break(1055)
Mar 13 11:43:51 server02 smbd[9136]:   request_oplock_break: no response 
received to oplock break request to pid 9134 on port 33103 for dev =
fd0
================
-- 
Paul Schoonderwoerd
Pollux IT - Open Source solutions & Netwerkbeveiliging
www.Pollux-IT.nl
Tel. 0294-283832